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Audit Complete

Results for https://jewishvirtuallibrary.org

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Brazil Brazil · Sao Paulo Completed: Apr 22, 2026 22:21 UTC
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Mobile 375 × 812

Screenshot of the audited page (Mobile 375×812)

Desktop 1440 × 900

Screenshot of the audited page (Desktop 1440×900)
D66

Site Health

Score: 66 / 100

Based on 8 categories, 0 sections

Room to improve — your 55.7s load time is above Google's 2.5s 'Good' threshold.

Several missing protections leave your users and data exposed.

Major barriers for users with disabilities — up to 15% of your audience.

Well-optimized for search — your content is discoverable.

Solid infrastructure — fast server responses across the board.

Several regulatory requirements are not yet met.

Rich content metadata — your pages look great everywhere.

Heavier than average — reducing page weight saves energy and bandwidth.

How is this calculated?

The overall score is a weighted average of individual category scores. Categories with more impact on user experience and security carry more weight.

Performance 25%Security 25%Accessibility 15%SEO 10%Infrastructure 10%Compliance 8%Content 5%Sustainability 2%

Weights reflect general web best practices. Individual needs may differ.

How the composite score is calculated

How you compare

Cloudflare Bot Management · 435 peers
You 66
·
Avg 74
-8 below average
0 50 100
Cloudflare Rocket Loader · 57 peers
You 66
·
Avg 74
-8 below average
0 50 100

Top Priorities (5)

1

Content-Security-Policy header is missing

Security gaps expose your site and users to attacks, eroding trust.

Security › Security Headers
2

Cookie 'ezfs_450841' is missing the Secure flag

Security gaps expose your site and users to attacks, eroding trust.

Security › Cookie Security
3

Cookie 'ezoictest' is missing the Secure flag

Security gaps expose your site and users to attacks, eroding trust.

Security › Cookie Security
4

HSTS header is missing

Security gaps expose your site and users to attacks, eroding trust.

Security › Security Headers
5

No Content-Security-Policy header found

Security gaps expose your site and users to attacks, eroding trust.

Security › Content Security Policy
View fix priority matrix

Fix Priority Matrix

5 findings

Quick Wins

5

High impact, low effort — start here.

Strategic

0

High impact, requires investment.

Nothing in this quadrant — good news.

Easy Improvements

0

Small gains, minimal effort.

Nothing in this quadrant — good news.

Deprioritize

0

Low impact, high effort — do last.

Nothing in this quadrant — good news.

← Low effort High effort →
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What fixing these means

Your site has several issues that may be affecting user experience and business outcomes. The 5 security gaps leave your users exposed — modern browsers increasingly warn visitors about insecure sites. Addressing the critical issues below would have the most immediate impact on your user trust.

5 security gaps detected — browsers may warn visitors about your site.

Conversion Barriers

2 critical 8 warning

10 barrier(s) likely increasing bounce by ~31%.

Speed (2)

Page takes 55.7s to load

+12% bounce

Users abandon at ~3s — you're 53.2s over the 2.5s threshold

Fix: Optimize render-blocking resources, preload the hero image, and compress images

Page feels frozen for 8.9s

+5% bounce

Clicks on the primary CTA are ignored while JavaScript runs

Fix: Break up long tasks; defer non-critical JavaScript to post-hydration

Trust (2)

No HSTS header

+1% bounce

Returning visitors are briefly exposed to downgrade attacks on first request

Fix: Set Strict-Transport-Security: max-age=31536000; includeSubDomains

No Content-Security-Policy header

+1% bounce

Higher XSS blast radius — one compromised script can exfiltrate the checkout form

Fix: Ship a reporting-only CSP first, then enforce once violations are clean

Usability (1)

Layout shifts during page load

+3% bounce

Content movement causes mis-clicks on CTAs and form fields

Fix: Add width/height to images; reserve space for late-loading embeds

Content (2)

No structured data

+2% bounce

No rich-result eligibility in Google — lower SERP CTR vs competitors with stars and prices

Fix: Add JSON-LD for your page type (Product, Article, FAQPage, LocalBusiness, …)

Content is hard to read

+2% bounce

Graduate-level reading difficulty — limits the addressable audience for product or blog pages

Fix: Shorten sentences; replace jargon with plain language; target Flesch ease ≥60

Navigation (3)

10 link(s) with generic text ("click here", "read more")

+1% bounce

Screen-reader users navigating by link list see no context — and search engines can't infer relevance

Fix: Rewrite with descriptive phrases that identify the destination

No skip-to-content link

+1% bounce

Keyboard and screen-reader users must tab through the entire header on every page

Fix: Add a visible-on-focus <a href="#main">Skip to content</a> as the first focusable element

1 broken link(s) on the page

+2% bounce

Clicks land on 404s — trust drops and the session often ends

Fix: Fix or remove the broken destinations surfaced on the Content tab

Preliminary CRO audit — each barrier links to the tab with detailed analysis.

Return on Investment

$250 investment → $4.25/month returns + USD 157,500 risk avoided

Payback period: > 2 years First-year ROI: -80%

Investment

$250

2h · 5 findings

Monthly returns

$4.25 /mo

~$51 / year

  • Bandwidth savings $4.25

Regulatory risk avoided

USD 157,500

if kept compliant

  • ADA Title III USD 150,000
  • CCPA/CPRA USD 7,500

Figures combine localized regulatory fine ceilings, search/conversion value priced against local CPC, and bandwidth waste estimates. Results depend on implementation quality and audience composition. Not legal or financial advice.

Full methodology & sources

Estimated Remediation Cost

$250

2.5 developer hours at $100/hr

Based on United States rates ($100/hr)

Quick wins
$250 5 fixes in ~150 minutes

Start here for the best return on investment

Cost by category

Cost by effort level

Adjust assumptions
$ /hr

Rates reflect fully-loaded developer cost including overhead

How developer rates are sourced

What Inaction Is Costing You

$13,129 / month at risk

~$157,551 / year if left unfixed

Compliance Risk

$157,500

ADA Title IIICCPA/CPRA
  • No privacy policy link detected
    CCPA/CPRA: USD 2,500 – USD 7,500
  • Trackers detected but no cookie policy found
    CCPA/CPRA: USD 2,500 – USD 7,500
  • Trackers detected but no privacy policy found
    CCPA/CPRA: USD 2,500 – USD 7,500

+7 more

Bandwidth Waste

$4.25 /mo

53082.8 MB/mo × 0.080 USD/GB

  • Optimize transfer: save ~5.3 MB per page load
    Saves $4.25/mo

Compliance figures represent the statutory maximum fine for the most severe triggered category, capped per regulation — not the sum of per-finding penalties. Based on published regulatory fine ranges. This is not legal advice.

Compliance methodology · SEO assumptions · Bandwidth model

Your performance is already good — improvements may show diminishing returns

Unique monthly visitors from your analytics

Purchases, signups, or key actions

Optional — for revenue estimation

additional conversions/month

more engaged visitors from reduced bounce

potential monthly revenue
Current bounce (est.)
After fixes (est.)
Estimated bounce reduction

Fix 5 critical issues to capture this value

How this is calculated

Based on Google/Deloitte research ("Milliseconds Make Millions") showing a ~7% bounce rate increase per additional second of LCP above the 2.5s "Good" threshold.

Your site's LCP: → estimated after fixes.

These are estimates based on industry research — actual results vary

Bounce-rate model & assumptions

Your data stays in your browser — nothing is sent to our servers

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Lighthouse Scores

Industry-standard audits powered by Google Lighthouse.

16
Performance Overall performance score (0–100) based on Core Web Vitals and other metrics. 90+ is good.
75
Accessibility Measures how accessible the page is for users with disabilities. Checks color contrast, ARIA labels, and semantic HTML.
77
Best Practices Checks for modern web development best practices including HTTPS, no console errors, and secure JavaScript.
83
SEO Measures basic SEO optimizations: meta tags, crawlability, link text, and mobile friendliness.

Core Web Vitals

Key metrics that affect user experience.

First Contentful Paint First Contentful Paint — how long until the browser renders the first piece of content. Under 1.8s is good.

5.13 s

Largest Contentful Paint Largest Contentful Paint — how long until the largest visible element loads. Under 2.5s is good.

55.74 s

Total Blocking Time Total Blocking Time — total time the main thread was blocked, preventing user input. Under 200ms is good.

8.90 s

Cumulative Layout Shift Cumulative Layout Shift — measures visual stability. How much the page layout shifts during loading. Under 0.1 is good.

0.199

Speed Index Speed Index — how quickly content is visually displayed during load. Under 3.4s is good.

20.51 s

Time to Interactive Time to Interactive — how long until the page is fully interactive and responds to user input. Under 3.8s is good.

85.64 s

Detailed Report

Audit breakdown by category with detailed findings.

16

Performance

Insights

Remove large, duplicate JavaScript modules from bundles to reduce unnecessary bytes consumed by network activity.

Why this matters

Performance issues directly impact user engagement and conversion rates.

Polyfills and transforms enable older browsers to use new JavaScript features. However, many aren't necessary for modern browsers. Consider modifying your JavaScript build process to not transpile Baseline features, unless you know you must support older browsers. Learn why most sites can deploy ES6+ code without transpiling

Why this matters

Shipping ES5 transpiled code to modern browsers wastes bytes — every user with an evergreen browser pays for compatibility you don't need.

Learn more

Most users today run browsers that natively support ES6+, async/await, optional chaining, and the rest of modern JavaScript. Transpiling to ES5 'just in case' adds 20-40% to your bundle for no benefit. Configure your build to target a modern browserslist, or ship a differential bundle pair (modern + legacy) with the module/nomodule pattern.

Source: Google web.dev / Lighthouse

3rd party code can significantly impact load performance. Reduce and defer loading of 3rd party code to prioritize your page's content.

Why this matters

Performance issues directly impact user engagement and conversion rates.

A long cache lifetime can speed up repeat visits to your page. Learn more about caching.

Why this matters

Performance issues directly impact user engagement and conversion rates.

RequestCache TTLTransfer Size
www.ezojs.com/identity.js900.0 s101.7 KiB
connect.facebook.net/en_US/fbevents.js1200.0 s96.6 KiB
client.aps.amazon-adsystem.com/publisher.js3600.0 s82.4 KiB
www.ezojs.com/ezoic/sa.min.js600.0 s65.8 KiB
/pagead/managed/js/activeview/current/ufs_web_display.js3600.0 s73.1 KiB
go.ezodn.com/ezoic/ezorca.min.js14400.0 s74.3 KiB
/signals/config/973535300821278?v=2.9.303&r=stable&domain...1200.0 s45.9 KiB
static.ctctcdn.com/js/signup-form-widget/current/signup-form-widget.min.js900.0 s37.2 KiB
cdn.id5-sync.com/api/1.0/id5-api.js3600.0 s34.6 KiB
cdn.id5-sync.com/api/1.0/id5PrebidModule.js3600.0 s29.4 KiB
/mysidia/23d6fddffbfbc0c895172a6366be7687.js?tag=video_mr...86400.0 s54.6 KiB
/mysidia/407ec6ab7422a4db180789e005c9d251.js?tag=video_mr...86400.0 s54.2 KiB
/accounts/21528/uploads/pollswebinar-b22b87b59a6989e21407...1209600.0 s203.0 KiB
s0.2mdn.net/879366/express_html_inpage_rendering_lib_200_287.js86400.0 s40.9 KiB
www.google-analytics.com/analytics.js7200.0 s20.9 KiB
ep2.adtrafficquality.google/sodar/VFc2VJAc.js3000.0 s14.0 KiB
img.youtube.com/vi/eMSe4VZlxHI/hqdefault.jpg7200.0 s11.2 KiB
/cdn-cgi/challenge-platform/h/b/scripts/jsd/0b8fb825cb67/...14400.0 s11.9 KiB
cdn.popupsmart.com/uploaded/df75579e750a8914435fe976c4a24fda.jpeg1209600.0 s79.0 KiB
connectid.analytics.yahoo.com/connectId-gpt.js3600.0 s9.0 KiB
tagan.adlightning.com/ezoic-3/op.js3600.0 s8.8 KiB
/mysidia/9475976b3d2af33fba37207c76515039.js?tag=addon/my...86400.0 s16.7 KiB
static.criteo.net/js/ld/publishertag.ids.js86400.0 s14.8 KiB
eus.rubiconproject.com/usync.js46613.0 s11.5 KiB
tags.crwdcntrl.net/lt/c/16589/sync.min.js86400.0 s13.5 KiB
static.ctctcdn.com/js/signup-form-widget/current/signup-form-widget.css900.0 s5.7 KiB
cdn.popupsmart.com/uploaded/f6323896112abba738f0b5339d195f61.png1209600.0 s45.0 KiB
cdn.popupsmart.com/uploaded/c742c2a17d1ae14429efe5a97edebd41.png1209600.0 s36.9 KiB
a.amxrtb.com/js/cframe.js#gdpr=0&gdpr_consent=&cc=BR14400.0 s5.1 KiB
/cdn-cgi/scripts/7d0fa10a/cloudflare-static/rocket-loader...2849.0 s3.9 KiB
the.gatekeeperconsent.com/cmp.min.js300.0 s3.0 KiB
invstatic101.creativecdn.com/encrypted-signals/encrypted-tag-g.js0.0 ms2.9 KiB
config.aps.amazon-adsystem.com/configs/aa05931b-5308-4ea3-95a2-adf84f4ffde43600.0 s2.9 KiB
cdn.popupsmart.com/uploaded/6cfed2455a4615d599e69c1ca3cbc3d7.jpeg1209600.0 s13.5 KiB
pagead2.googlesyndication.com/pagead/js/r20260421/r20110914/abg_lite.js1209600.0 s10.5 KiB
id5-sync.com/c/457/0/8/1.gif?gdpr=0&gdpr_consent=&us_privacy=0.0 ms1.0 KiB
id5-sync.com/c/457/0/8/1.gif?gdpr=0&gdpr_consent=&us_privacy=0.0 ms1.0 KiB
/pagead/js/r20260422/r20110914/elements/html/interstitial...1209600.0 s9.8 KiB
/pagead/js/r20260422/r20110914/client/qs_click_protection...1209600.0 s8.6 KiB
/pagead/js/r20260421/r20110914/client/qs_click_protection...1209600.0 s8.5 KiB
cmp.gatekeeperconsent.com/min.js0.0 ms852 B
tpc.googlesyndication.com/pagead/js/r20260421/r20110914/abg_lite_fy2021.js1209600.0 s8.4 KiB
go.ezodn.com/utilcave_com/ezoicbwa.png86400.0 s1.8 KiB
cdn.popupsmart.com/uploaded/f81012b28668e613ce9719390e694fc0.png1209600.0 s6.8 KiB
cdn.popupsmart.com/assets/empty.png1209600.0 s6.8 KiB
/pagead/js/r20260422/r20110914/elements/html/fullscreen_a...1209600.0 s6.7 KiB
rules.quantcount.com/rules-p-31iz6hfFutd16.js3600.0 s630 B
/mysidia/eb506c874c4df599e8b527ba6b052c54.js?tag=engine/c...86400.0 s1.2 KiB
/pagead/js/r20260421/r20110914/elements/html/omrhp.js1209600.0 s4.7 KiB
link.rubiconproject.com/magnite/21150.js45800.0 s855 B
d9.flashtalking.com/img/img.png?cnx=4153cefa2085875d29c6fe925d5b24dd0.0 ms241 B
/pagead/js/r20260422/r20110914/client/window_focus_fy2021.js1209600.0 s1.3 KiB
/pagead/js/r20260421/r20110914/client/window_focus_fy2021.js1209600.0 s1.2 KiB
cdn.jsdelivr.net/gh/prebid/shared-id/pubcid.js/docs/pubcid.min.js604800.0 s981 B
/pagead/js/r20260421/r20110914/client/load_preloaded_reso...1209600.0 s840 B
/tr/?id=973535300821278&ev=Purchase&dl=https%3A%2F%2Fjewi...0.0 ms16 B
/mysidia/9475976b3d2af33fba37207c76515039.js?tag=addon/my...86400.0 s0 B
tpc.googlesyndication.com/pagead/js/r20260421/r20110914/abg_lite_fy2021.js1209600.0 s0 B
/pagead/js/r20260421/r20110914/client/qs_click_protection...1209600.0 s0 B
img.youtube.com/vi/eMSe4VZlxHI/hqdefault.jpg7200.0 s0 B
/pagead/js/r20260421/r20110914/client/window_focus_fy2021.js1209600.0 s0 B
/mysidia/eb506c874c4df599e8b527ba6b052c54.js?tag=engine/c...86400.0 s0 B
/pagead/js/r20260421/r20110914/client/load_preloaded_reso...1209600.0 s0 B

Layout shifts occur when elements move absent any user interaction. Investigate the causes of layout shifts, such as elements being added, removed, or their fonts changing as the page loads.

Why this matters

Performance issues directly impact user engagement and conversion rates.

headings: [map[key:node label:Element subItemsHeading:map[key:extra] valueType:node] map[granularity:0.001 key:score label:Layout shift score subItemsHeading:map[key:cause valueType:text] valueType:numeric]]
items: [map[node:map[type:text value:Total] score:0.023239] map[node:map[boundingRect:map[bottom:2261 height:84 left:10 right:403 top:2177 width:393] lhId:page-20-DIV nodeLabel:EXPLORE path:1,HTML,1,BODY,2,DIV,0,DIV,3,DIV,2,DIV,2,DIV,0,DIV,0,DIV,2,DIV,1,DIV,0,DIV,1,DIV,2,DIV selector:div.bg-flesh > div.d-flex > div.d-flex > div.justify-content-center snippet:<div class="justify-content-center d-flex justify-content-center align-items-center te…" data-v-63a325e7=""> type:node] score:0.022976 subItems:map[items:[map[cause:Unsized image element extra:map[boundingRect:map[bottom:2121 height:247 left:21 right:391 top:1874 width:371] lhId:page-2-IMG nodeLabel:div.d-flex > div.d-flex > div.d-flex > img.m-2 path:1,HTML,1,BODY,2,DIV,0,DIV,3,DIV,2,DIV,2,DIV,0,DIV,0,DIV,2,DIV,1,DIV,0,DIV,1,DIV,0,DIV,0,IMG selector:div.d-flex > div.d-flex > div.d-flex > img.m-2 snippet:<img src="/_nuxt/ancient-jewish-history.CH0rC6of.webp" class="m-2" style="box-shadow:5px 5px 0px 0px #C38D00;" data-v-63a325e7=""> type:node]]] type:subitems]] map[node:map[boundingRect:map[bottom:155 height:42 left:190 right:377 top:113 width:187] lhId:page-22-DIV nodeLabel:div#header > div.d-flex > div.d-flex > div.search-container path:1,HTML,1,BODY,2,DIV,0,DIV,1,DIV,2,DIV,1,DIV,0,DIV selector:div#header > div.d-flex > div.d-flex > div.search-container snippet:<div class="search-container d-flex justify-content-end" data-v-f80de7ef="" data-v-4b72c19a=""> type:node] score:0.000263 subItems:map[items:[map[cause:Unsized image element extra:map[boundingRect:map[bottom:2121 height:247 left:21 right:391 top:1874 width:371] lhId:page-2-IMG nodeLabel:div.d-flex > div.d-flex > div.d-flex > img.m-2 path:1,HTML,1,BODY,2,DIV,0,DIV,3,DIV,2,DIV,2,DIV,0,DIV,0,DIV,2,DIV,1,DIV,0,DIV,1,DIV,0,DIV,0,IMG selector:div.d-flex > div.d-flex > div.d-flex > img.m-2 snippet:<img src="/_nuxt/ancient-jewish-history.CH0rC6of.webp" class="m-2" style="box-shadow:5px 5px 0px 0px #C38D00;" data-v-63a325e7=""> type:node]]] type:subitems]]]
headings: [map[key:node label:Element subItemsHeading:map[key:extra] valueType:node] map[granularity:0.001 key:score label:Layout shift score subItemsHeading:map[key:cause valueType:text] valueType:numeric]]
items: [map[node:map[type:text value:Total] score:0.198803] map[node:map[boundingRect:map[bottom:3085 height:1371 left:0 right:412 top:1714 width:412] lhId:page-23-DIV nodeLabel:HISTORICAL TIMELINES Discover key moments in Jewish history, from ancient times… path:1,HTML,1,BODY,2,DIV,0,DIV,3,DIV,2,DIV,2,DIV selector:div > div.row > div.text-black > div.text-black snippet:<div class="text-black row d-flex py-5 px-5"> type:node] score:0.198363 subItems:map[items:[map[cause:Unsized image element extra:map[boundingRect:map[bottom:2121 height:247 left:21 right:391 top:1874 width:371] lhId:page-2-IMG nodeLabel:div.d-flex > div.d-flex > div.d-flex > img.m-2 path:1,HTML,1,BODY,2,DIV,0,DIV,3,DIV,2,DIV,2,DIV,0,DIV,0,DIV,2,DIV,1,DIV,0,DIV,1,DIV,0,DIV,0,IMG selector:div.d-flex > div.d-flex > div.d-flex > img.m-2 snippet:<img src="/_nuxt/ancient-jewish-history.CH0rC6of.webp" class="m-2" style="box-shadow:5px 5px 0px 0px #C38D00;" data-v-63a325e7=""> type:node]]] type:subitems]] map[node:map[boundingRect:map[bottom:155 height:42 left:190 right:377 top:113 width:187] lhId:page-22-DIV nodeLabel:div#header > div.d-flex > div.d-flex > div.search-container path:1,HTML,1,BODY,2,DIV,0,DIV,1,DIV,2,DIV,1,DIV,0,DIV selector:div#header > div.d-flex > div.d-flex > div.search-container snippet:<div class="search-container d-flex justify-content-end" data-v-f80de7ef="" data-v-4b72c19a=""> type:node] score:0.00044 subItems:map[items:[map[cause:Unsized image element extra:map[boundingRect:map[bottom:2121 height:247 left:21 right:391 top:1874 width:371] lhId:page-2-IMG nodeLabel:div.d-flex > div.d-flex > div.d-flex > img.m-2 path:1,HTML,1,BODY,2,DIV,0,DIV,3,DIV,2,DIV,2,DIV,0,DIV,0,DIV,2,DIV,1,DIV,0,DIV,1,DIV,0,DIV,0,IMG selector:div.d-flex > div.d-flex > div.d-flex > img.m-2 snippet:<img src="/_nuxt/ancient-jewish-history.CH0rC6of.webp" class="m-2" style="box-shadow:5px 5px 0px 0px #C38D00;" data-v-63a325e7=""> type:node]] map[cause:Web font extra:map[type:url value:https://fonts.gstatic.com/s/roboto/v51/KFOMCnqEu92Fr1ME7kSn66aGLdTylUAMQXC89YmC2DPNWubEbVmUiAr0lFQm.woff2]]] type:subitems]]]
headings: [map[key:node label:Element subItemsHeading:map[key:extra] valueType:node] map[granularity:0.001 key:score label:Layout shift score subItemsHeading:map[key:cause valueType:text] valueType:numeric]]
items: [map[node:map[type:text value:Total] score:0.004457] map[node:map[boundingRect:map[bottom:845 height:108 left:0 right:423 top:737 width:423] lhId:page-27-INS nodeLabel:Advertisement path:1,HTML,20,INS selector:ins#gpt_unit_/23057360293,22907843112/jewishvirtuallibrary_org-medrectangle-2_0 snippet:<ins id="gpt_unit_/23057360293,22907843112/jewishvirtuallibrary_org-medrectangle-2_0" data-google-query-id="COW8g_6-gpQDFdVSuAQdD_EA9A" data-anchor-status="displayed" data-anchor-shown="true" style="display: block; max-width: none; width: 100% !important;"> type:node] score:0.000718] map[node:map[boundingRect:map[bottom:845 height:108 left:0 right:423 top:737 width:423] lhId:page-27-INS nodeLabel:Advertisement path:1,HTML,20,INS selector:ins#gpt_unit_/23057360293,22907843112/jewishvirtuallibrary_org-medrectangle-2_0 snippet:<ins id="gpt_unit_/23057360293,22907843112/jewishvirtuallibrary_org-medrectangle-2_0" data-google-query-id="COW8g_6-gpQDFdVSuAQdD_EA9A" data-anchor-status="displayed" data-anchor-shown="true" style="display: block; max-width: none; width: 100% !important;"> type:node] score:0.000664 subItems:map[items:[map[cause:Unsized image element extra:map[boundingRect:map[bottom:2121 height:247 left:21 right:391 top:1874 width:371] lhId:page-2-IMG nodeLabel:div.d-flex > div.d-flex > div.d-flex > img.m-2 path:1,HTML,1,BODY,2,DIV,0,DIV,3,DIV,2,DIV,2,DIV,0,DIV,0,DIV,2,DIV,1,DIV,0,DIV,1,DIV,0,DIV,0,IMG selector:div.d-flex > div.d-flex > div.d-flex > img.m-2 snippet:<img src="/_nuxt/ancient-jewish-history.CH0rC6of.webp" class="m-2" style="box-shadow:5px 5px 0px 0px #C38D00;" data-v-63a325e7=""> type:node]]] type:subitems]] map[node:map[boundingRect:map[bottom:845 height:103 left:6 right:418 top:742 width:412] lhId:page-28-IFRAME nodeLabel:Advertisement path:1,HTML,20,INS,1,DIV,0,IFRAME selector:ins#gpt_unit_/23057360293,22907843112/jewishvirtuallibrary_org-medrectangle-2_0 > div#google_ads_iframe_/23057360293,22907843112/jewishvirtuallibrary_org-medrectangle-2_0__container__ > iframe#google_ads_iframe_/23057360293,22907843112/jewishvirtuallibrary_org-medrectangle-2_0 snippet:<iframe frameborder="0" src="https://acb0ba6c5abc3caf78d7c1f9d1ae2427.safeframe.googlesyndication.com/s…" id="google_ads_iframe_/23057360293,22907843112/jewishvirtuallibrary_org-medrec…" name="" scrolling="no" marginwidth="0" marginheight="0" width="412" height="103" data-is-safeframe="true" sandbox="allow-forms allow-popups allow-popups-to-escape-sandbox allow-same-origin …" allow="private-state-token-redemption;attribution-reporting" aria-label="Advertisement" tabindex="0" data-google-container-id="1" style="border: 0px; vertical-align: bottom; max-height: 50vh !important;" …> type:node] score:0.000658] map[node:map[boundingRect:map[bottom:845 height:108 left:0 right:423 top:737 width:423] lhId:page-27-INS nodeLabel:Advertisement path:1,HTML,20,INS selector:ins#gpt_unit_/23057360293,22907843112/jewishvirtuallibrary_org-medrectangle-2_0 snippet:<ins id="gpt_unit_/23057360293,22907843112/jewishvirtuallibrary_org-medrectangle-2_0" data-google-query-id="COW8g_6-gpQDFdVSuAQdD_EA9A" data-anchor-status="displayed" data-anchor-shown="true" style="display: block; max-width: none; width: 100% !important;"> type:node] score:0.000568] map[node:map[boundingRect:map[bottom:845 height:108 left:0 right:423 top:737 width:423] lhId:page-27-INS nodeLabel:Advertisement path:1,HTML,20,INS selector:ins#gpt_unit_/23057360293,22907843112/jewishvirtuallibrary_org-medrectangle-2_0 snippet:<ins id="gpt_unit_/23057360293,22907843112/jewishvirtuallibrary_org-medrectangle-2_0" data-google-query-id="COW8g_6-gpQDFdVSuAQdD_EA9A" data-anchor-status="displayed" data-anchor-shown="true" style="display: block; max-width: none; width: 100% !important;"> type:node] score:0.000496]]

Consider setting font-display to swap or optional to ensure text is consistently visible. swap can be further optimized to mitigate layout shifts with font metric overrides.

Why this matters

Performance issues directly impact user engagement and conversion rates.

A forced reflow occurs when JavaScript queries geometric properties (such as offsetWidth) after styles have been invalidated by a change to the DOM state. This can result in poor performance. Learn more about forced reflows and possible mitigations.

Why this matters

Performance issues directly impact user engagement and conversion rates.

headings: [map[key:source label:Top function call valueType:source-location] map[granularity:1 key:reflowTime label:Total reflow time valueType:ms]]
items: [map[reflowTime:11.695 source:map[column:24639 line:1 type:source-location url:https://go.ezodn.com/ezoic/ezorca.min.js urlProvider:network]]]
headings: [map[key:source label:Source valueType:source-location] map[granularity:1 key:reflowTime label:Total reflow time valueType:ms]]
items: [map[reflowTime:46.881 source:map[type:text value:[unattributed]]] map[reflowTime:33.465 source:map[column:18 line:44 type:source-location url: urlProvider:network]] map[reflowTime:11.695 source:map[column:23774 line:0 type:source-location url:https://go.ezodn.com/ezoic/ezorca.min.js urlProvider:network]] map[reflowTime:0.503 source:map[column:163 line:18 type:source-location url:https://go.ezodn.com/hb/dall.js?cb=195-1-157 urlProvider:network]] map[reflowTime:0.152 source:map[column:48217 line:18 type:source-location url:https://securepubads.g.doubleclick.net/pagead/managed/js/gpt/m202604200101/pubads_impl.js?cb=31098007 urlProvider:network]] map[reflowTime:2.453 source:map[column:241859 line:18 type:source-location url:https://securepubads.g.doubleclick.net/pagead/managed/js/gpt/m202604200101/pubads_impl.js?cb=31098007 urlProvider:network]] map[reflowTime:0.546 source:map[column:61643 line:18 type:source-location url:https://securepubads.g.doubleclick.net/pagead/managed/js/gpt/m202604200101/pubads_impl.js?cb=31098007 urlProvider:network]] map[reflowTime:1.919 source:map[column:575316 line:18 type:source-location url:https://securepubads.g.doubleclick.net/pagead/managed/js/gpt/m202604200101/pubads_impl.js?cb=31098007 urlProvider:network]]]

Reducing the download time of images can improve the perceived load time of the page and LCP. Learn more about optimizing image size

Why this matters

Performance issues directly impact user engagement and conversion rates.

URLResource SizeEst Savings
div.d-flex > div.d-flex > div.d-flex > img.m-2 div.d-flex > div.d-flex > div.d-flex > img.m-2
jewishvirtuallibrary.org/_nuxt/modern-jewish-history.B275WmxT.webp352.8 KiB306.1 KiB
Popup Image div > div > div#image-cr089nawhnc0 > img
/accounts/21528/uploads/pollswebinar-b22b87b59a6989e21407...202.1 KiB137.7 KiB
div.d-flex > div.d-flex > div.d-flex > img.m-2 div.d-flex > div.d-flex > div.d-flex > img.m-2
jewishvirtuallibrary.org/_nuxt/ancient-jewish-history.CH0rC6of.webp134.1 KiB88.4 KiB
swiper-slide > a.cursor-pointer > div.border-solid > img.object-cover swiper-slide > a.cursor-pointer > div.border-solid > img.object-cover
/storage/uploads/wing/11/1be41f9b-1f29-4b69-9a74-6ceb724e...110.0 KiB66.9 KiB
swiper-slide > a.cursor-pointer > div.border-solid > img.object-cover swiper-slide > a.cursor-pointer > div.border-solid > img.object-cover
/storage/uploads/wing/3/6c87d582-e993-4811-9f24-1234b0b51...79.6 KiB49.6 KiB
div.d-flex > div.d-flex > div.col > img.p-8 div.d-flex > div.d-flex > div.col > img.p-8
jewishvirtuallibrary.org/_nuxt/IsraelFlag.DqZRK-Do.jpeg63.0 KiB45.5 KiB
div#header > div.d-flex > div.col > img.logo div#header > div.d-flex > div.col > img.logo
jewishvirtuallibrary.org/_nuxt/jvl-logo-white.BD6jMrbI.png40.8 KiB39.5 KiB
div.d-flex > div.d-flex > div.d-flex > img.m-2 div.d-flex > div.d-flex > div.d-flex > img.m-2
jewishvirtuallibrary.org/_nuxt/history-of-jerusalem.C77BYNka.png81.6 KiB35.5 KiB
swiper-slide > a.cursor-pointer > div.border-solid > img.object-cover swiper-slide > a.cursor-pointer > div.border-solid > img.object-cover
/storage/uploads/wing/7/f848b9d2-13d0-4e83-a1eb-851805e8a...66.9 KiB35.4 KiB
swiper-slide.swiper-slide-active > a.cursor-pointer > div.border-solid > img.object-cover swiper-slide.swiper-slide-active > a.cursor-pointer > div.border-solid > img.object-cover
/storage/uploads/wing/1/48f62870-07ac-48fe-a253-9ee4fc3f3...74.2 KiB31.2 KiB
div.d-flex > div.d-flex > div.col > img.p-8 div.d-flex > div.d-flex > div.col > img.p-8
jewishvirtuallibrary.org/_nuxt/world-map.LtxKRr9f.jpg42.6 KiB30.8 KiB
swiper-slide > a.cursor-pointer > div.border-solid > img.object-cover swiper-slide > a.cursor-pointer > div.border-solid > img.object-cover
/storage/uploads/wing/5/41d3ba5f-a76a-4f5a-aa24-f5568839b...60.6 KiB17.6 KiB
swiper-slide > a.cursor-pointer > div.border-solid > img.object-cover swiper-slide > a.cursor-pointer > div.border-solid > img.object-cover
/storage/uploads/wing/13/17e59cc1-7d9c-4d9f-9e90-1d843ccd...55.0 KiB17.4 KiB
swiper-slide > a.cursor-pointer > div.border-solid > img.object-cover swiper-slide > a.cursor-pointer > div.border-solid > img.object-cover
/storage/uploads/wing/9/53f4f324-9f62-41af-8df1-b514d5155...46.0 KiB15.6 KiB
swiper-slide > a.cursor-pointer > div.border-solid > img.object-cover swiper-slide > a.cursor-pointer > div.border-solid > img.object-cover
/storage/uploads/wing/12/b3f3c705-2e4e-4b0e-9ff6-a05bcc99...58.3 KiB15.3 KiB
swiper-slide > a.cursor-pointer > div.border-solid > img.object-cover swiper-slide > a.cursor-pointer > div.border-solid > img.object-cover
/storage/uploads/wing/10/27418e5a-1536-4f97-b368-fac9fc9d...32.1 KiB13.7 KiB
swiper-slide > a.cursor-pointer > div.border-solid > img.object-cover swiper-slide > a.cursor-pointer > div.border-solid > img.object-cover
/storage/uploads/wing/15/50cc2757-2bcf-491f-a136-0ea1bc3b...53.3 KiB9.6 KiB
swiper-slide > a.cursor-pointer > div.border-solid > img.object-cover swiper-slide > a.cursor-pointer > div.border-solid > img.object-cover
/storage/uploads/wing/14/85c365b9-f034-453b-977d-535b9cc6...15.7 KiB8.0 KiB
swiper-slide > a.cursor-pointer > div.border-solid > img.object-cover swiper-slide > a.cursor-pointer > div.border-solid > img.object-cover
/storage/uploads/wing/8/ca81734c-3360-43ca-80c8-a74187507...36.1 KiB5.8 KiB

Optimize LCP by making the LCP image discoverable from the HTML immediately, and avoiding lazy-loading

Why this matters

Performance issues directly impact user engagement and conversion rates.

lhId: page-19-IMG
nodeLabel: div.col > swiper-container.slide-container > swiper-slide#slide > img.w-full
path: 1,HTML,1,BODY,2,DIV,0,DIV,3,DIV,2,DIV,0,DIV,2,DIV,1,SWIPER-CONTAINER,0,SWIPER-SLIDE,0,IMG
selector: div.col > swiper-container.slide-container > swiper-slide#slide > img.w-full
snippet: <img data-v-db7a4aa6="" src="https://jewishvirtuallibrary.org/_nuxt/monkmap-1.BOODmNVO.png" class="w-full object-contain slide-img">

Avoid chaining critical requests by reducing the length of chains, reducing the download size of resources, or deferring the download of unnecessary resources to improve page load.

Why this matters

Performance issues directly impact user engagement and conversion rates.

description: [preconnect](https://developer.chrome.com/docs/lighthouse/performance/uses-rel-preconnect/) hints help the browser establish a connection earlier in the page load, saving time when the first request for that origin is made. The following are the origins that the page preconnected to.
title: Preconnected origins
description: Add [preconnect](https://developer.chrome.com/docs/lighthouse/performance/uses-rel-preconnect/) hints to your most important origins, but try to use no more than 4.
title: Preconnect candidates

Requests are blocking the page's initial render, which may delay LCP. Deferring or inlining can move these network requests out of the critical path.

Why this matters

Performance issues directly impact user engagement and conversion rates.

These insights are also available in the Chrome DevTools Performance Panel - record a trace to view more detailed information.

Time to Interactive is the amount of time it takes for the page to become fully interactive. Learn more about the Time to Interactive metric.

Why this matters

Performance issues directly impact user engagement and conversion rates.

TTI

The maximum potential First Input Delay that your users could experience is the duration of the longest task. Learn more about the Maximum Potential First Input Delay metric.

Why this matters

Performance issues directly impact user engagement and conversion rates.

These are the largest layout shifts observed on the page. Each table item represents a single layout shift, and shows the element that shifted the most. Below each item are possible root causes that led to the layout shift. Some of these layout shifts may not be included in the CLS metric value due to windowing. Learn how to improve CLS

Why this matters

Performance issues directly impact user engagement and conversion rates.

ElementLayout shift score
HISTORICAL TIMELINES Discover key moments in Jewish history, from ancient times… div > div.row > div.text-black > div.text-black
0.198
EXPLORE div.bg-flesh > div.d-flex > div.d-flex > div.justify-content-center
0.023
Advertisement ins#gpt_unit_/23057360293,22907843112/jewishvirtuallibrary_org-medrectangle-2_0
0.001
Advertisement ins#gpt_unit_/23057360293,22907843112/jewishvirtuallibrary_org-medrectangle-2_0
0.001
Advertisement ins#gpt_unit_/23057360293,22907843112/jewishvirtuallibrary_org-medrectangle-2_0 > div#google_ads_iframe_/23057360293,22907843112/jewishvirtuallibrary_org-medrectangle-2_0__container__ > iframe#google_ads_iframe_/23057360293,22907843112/jewishvirtuallibrary_org-medrectangle-2_0
0.001
Advertisement ins#gpt_unit_/23057360293,22907843112/jewishvirtuallibrary_org-medrectangle-2_0
0.001
Advertisement ins#gpt_unit_/23057360293,22907843112/jewishvirtuallibrary_org-medrectangle-2_0
0.000
div#header > div.d-flex > div.d-flex > div.search-container div#header > div.d-flex > div.d-flex > div.search-container
0.000
Advertisement ins#gpt_unit_/23057360293,22907843112/jewishvirtuallibrary_org-medrectangle-2_0
0.000
div#header > div.d-flex > div.d-flex > div.search-container div#header > div.d-flex > div.d-flex > div.search-container
0.000
Advertisement ins#gpt_unit_/23057360293,22907843112/jewishvirtuallibrary_org-medrectangle-2_0
0.000
Advertisement ins#gpt_unit_/23057360293,22907843112/jewishvirtuallibrary_org-medrectangle-2_0
0.000
Advertisement ins#gpt_unit_/23057360293,22907843112/jewishvirtuallibrary_org-medrectangle-2_0
0.000
Advertisement ins#gpt_unit_/23057360293,22907843112/jewishvirtuallibrary_org-medrectangle-2_0
0.000
Advertisement ins#gpt_unit_/23057360293,22907843112/jewishvirtuallibrary_org-medrectangle-2_0
0.000

Diagnostics

Reduce unused rules from stylesheets and defer CSS not used for above-the-fold content to decrease bytes consumed by network activity. Learn how to reduce unused CSS.

Why this matters

Performance issues directly impact user engagement and conversion rates.

Reduce unused JavaScript and defer loading scripts until they are required to decrease bytes consumed by network activity. Learn how to reduce unused JavaScript.

Why this matters

Multi-megabyte JavaScript bundles delay every interactive feature on the page.

Learn more

This is the Lighthouse audit fired when too much JS is shipped relative to what executes. The fix isn't a config flag — it requires bundle analysis (webpack-bundle-analyzer, rollup-plugin-visualizer), splitting routes into chunks, lazy-loading off-screen components, and removing unused dependencies. Fundamentally different from minification: minifying reduces byte count, this reduces what's downloaded at all.

Source: Google web.dev / Lighthouse

Estimated savings: 2.5 s 2.3 MiB
URLTransfer SizeEst Savings
www.gstatic.com/recaptcha/releases/gTpTIWhbKpxADzTzkcabhXN4/recaptcha__en.js361.8 KiB161.8 KiB
go.ezodn.com/beardeddragon/wyvern.js?cb=191181.5 KiB161.0 KiB
cdn.popupsmart.com/accounts/21528/218978/22/main.js215.9 KiB156.0 KiB
cdn.popupsmart.com/accounts/21528/9928/14/main.js190.3 KiB138.6 KiB
cdn.popupsmart.com/accounts/21528/166618/8/main.js189.7 KiB136.0 KiB
cdn.popupsmart.com/accounts/21528/7495/21/main.js190.6 KiB135.9 KiB
cdn.popupsmart.com/accounts/21528/7337/21/main.js191.0 KiB132.4 KiB
go.ezodn.com/hb/dall.js?cb=195-1-157235.1 KiB120.6 KiB
imasdk.googleapis.com/js/sdkloader/ima3.js146.2 KiB110.5 KiB
www.googletagmanager.com/gtag/js?id=AW-16993759482&cx=c&gtm=4e64k0137.3 KiB101.5 KiB
/pagead/managed/js/gpt/m202604200101/pubads_impl.js?cb=31...187.7 KiB84.7 KiB
jewishvirtuallibrary.org/_nuxt/C7KtkeID.js148.7 KiB76.8 KiB
www.googletagmanager.com/gtag/js?id=G-PPRBG64R7T&cx=c&gtm=4e64k0174.6 KiB76.7 KiB
www.googletagmanager.com/gtm.js?id=GTM-MRW3HCKV143.2 KiB65.0 KiB
www.googletagmanager.com/gtag/js?id=UA-90790627-1124.9 KiB60.3 KiB
jewishvirtuallibrary.org/_nuxt/BAIthYij.js104.4 KiB59.0 KiB
www.ezojs.com/identity.js101.2 KiB57.9 KiB
www.googletagmanager.com/gtag/js?id=DC-15691174&cx=c&gtm=4e64k0129.1 KiB56.2 KiB
www.googletagmanager.com/gtag/js?id=AW-16993759482137.3 KiB51.4 KiB
go.ezodn.com/detroitchicago/portland.js?gcb=1&cb=c2dd6af0a365.4 KiB48.2 KiB
go.ezodn.com/detroitchicago/indy.js?cb=117&gcb=095.1 KiB47.8 KiB
client.aps.amazon-adsystem.com/publisher.js82.0 KiB45.0 KiB
go.ezodn.com/porpoiseant/ezadloadrewarded.js?cb=1048&gcb=195-162.5 KiB40.2 KiB
go.ezodn.com/beardeddragon/iguana.js?cb=f1a1972d0940.2 KiB37.1 KiB
jewishvirtuallibrary.org/_nuxt/CJr9Iqje.js75.6 KiB35.7 KiB
go.ezodn.com/beardeddragon/gilamonster.js?cb=a8e6cfba0b36.8 KiB35.0 KiB
static.ctctcdn.com/js/signup-form-widget/current/signup-form-widget.min.js36.7 KiB34.0 KiB
go.ezodn.com/ezoic/ezorca.min.js73.7 KiB34.0 KiB
connect.facebook.net/en_US/fbevents.js96.5 KiB33.1 KiB
www.ezojs.com/ezoic/sa.min.js65.3 KiB32.4 KiB
go.ezodn.com/beardeddragon/turtle.js?gcb=1&cb=25435cf23223.7 KiB21.9 KiB

Consider reducing the time spent parsing, compiling, and executing JS. You may find delivering smaller JS payloads helps with this. Learn how to reduce Javascript execution time.

Why this matters

Performance issues directly impact user engagement and conversion rates.

URLTotal CPU TimeScript EvaluationScript Parse
Unattributable4.3 s1.1 s0.0 ms
/pagead/managed/js/gpt/m202604200101/pubads_impl.js?cb=31...3.6 s3.3 s77 ms
/cdn-cgi/scripts/7d0fa10a/cloudflare-static/rocket-loader...2.6 s2.2 s9.8 ms
jewishvirtuallibrary.org/2.4 s170 ms23 ms
jewishvirtuallibrary.org/_nuxt/BAIthYij.js2.3 s656 ms0.7 ms
go.ezodn.com/detroitchicago/portland.js?gcb=1&cb=c2dd6af0a31.7 s1.6 s40 ms
go.ezodn.com/ezoic/ezorca.min.js1.1 s924 ms62 ms
jewishvirtuallibrary.org/porpoiseant/jellyfish.js?a=a&cb=21&dcb=195-1&shcb=341.0 s922 ms12 ms
jewishvirtuallibrary.org/_nuxt/CrUIaL8u.js797 ms756 ms0.7 ms
jewishvirtuallibrary.org/cdn-cgi/challenge-platform/scripts/jsd/main.js653 ms624 ms12 ms
www.gstatic.com/recaptcha/releases/gTpTIWhbKpxADzTzkcabhXN4/recaptcha__en.js648 ms347 ms111 ms
www.googletagmanager.com/gtag/js?id=DC-15691174&cx=c&gtm=4e64k0523 ms470 ms49 ms
tagan.adlightning.com/ezoic-3/b-cf5bcc9-3c36b56e.js511 ms445 ms9.5 ms
go.ezodn.com/hb/dall.js?cb=195-1-157465 ms361 ms92 ms
www.googletagmanager.com/gtag/js?id=AW-16993759482451 ms345 ms83 ms
client.aps.amazon-adsystem.com/publisher.js375 ms285 ms43 ms
www.googletagmanager.com/gtag/js?id=G-PPRBG64R7T&cx=c&gtm=4e64k0363 ms285 ms74 ms
go.ezodn.com/porpoiseant/ezhbvignette.js?cb=1048360 ms325 ms11 ms
cdn.popupsmart.com/bundle.js325 ms305 ms11 ms
tagan.adlightning.com/ezoic-3/op.js294 ms285 ms2.6 ms
www.googletagmanager.com/gtm.js?id=GTM-MRW3HCKV288 ms215 ms69 ms
ez-standalone.js281 ms273 ms0.0 ms
go.ezodn.com/detroitchicago/indy.js?cb=117&gcb=0249 ms204 ms43 ms
connect.facebook.net/en_US/fbevents.js212 ms166 ms44 ms
www.googletagmanager.com/gtag/js?id=UA-90790627-1212 ms162 ms48 ms
tagan.adlightning.com/ezoic-3/bl-0d6ee0c-300f8633.js203 ms156 ms46 ms
www.ezojs.com/ezoic/sa.min.js174 ms141 ms30 ms
www.ezojs.com/identity.js166 ms121 ms44 ms
imasdk.googleapis.com/js/sdkloader/ima3.js163 ms99 ms63 ms
/signals/config/973535300821278?v=2.9.303&r=stable&domain...162 ms137 ms24 ms
go.ezodn.com/beardeddragon/wyvern.js?cb=191159 ms76 ms82 ms
cdn.popupsmart.com/accounts/21528/218978/22/main.js144 ms132 ms4.8 ms
static.ctctcdn.com/js/signup-form-widget/current/signup-form-widget.min.js141 ms15 ms125 ms
cdn.popupsmart.com/accounts/21528/7337/21/main.js137 ms117 ms4.5 ms
go.ezodn.com/porpoiseant/ezadloadrewarded.js?cb=1048&gcb=195-1137 ms104 ms31 ms
cdn.popupsmart.com/accounts/21528/7495/21/main.js123 ms81 ms4.3 ms
cdn.id5-sync.com/api/1.0/id5-api.js122 ms95 ms15 ms
cdn.popupsmart.com/accounts/21528/166618/8/main.js112 ms82 ms4.3 ms
securepubads.g.doubleclick.net/tag/js/gpt.js109 ms93 ms15 ms
config.aps.amazon-adsystem.com/configs/aa05931b-5308-4ea3-95a2-adf84f4ffde4104 ms89 ms11 ms
ep2.adtrafficquality.google/sodar/sodar2.js102 ms92 ms2.7 ms
www.googletagmanager.com/gtag/js?id=AW-16993759482&cx=c&gtm=4e64k094 ms32 ms61 ms
static.criteo.net/js/ld/publishertag.ids.js63 ms54 ms7.9 ms
www.google-analytics.com/analytics.js63 ms55 ms6.8 ms
cdn.popupsmart.com/accounts/21528/9928/14/main.js60 ms45 ms6.2 ms
oa.openxcdn.net/esp.js52 ms46 ms3.2 ms

Consider reducing the time spent parsing, compiling and executing JS. You may find delivering smaller JS payloads helps with this. Learn how to minimize main-thread work

Why this matters

Performance issues directly impact user engagement and conversion rates.

CategoryTime Spent
Script Evaluation19.2 s
Other5.4 s
Style & Layout1.7 s
Script Parsing & Compilation1.7 s
Garbage Collection681 ms
Rendering637 ms
Parse HTML & CSS324 ms

Many navigations are performed by going back to a previous page, or forwards again. The back/forward cache (bfcache) can speed up these return navigations. Learn more about the bfcache

Why this matters

Performance issues directly impact user engagement and conversion rates.

Failure reasonFailure type
The page has an unload handler in the main frame.Actionable
Pages with cache-control:no-store header cannot enter back/forward cache.Actionable
Pages whose main resource has cache-control:no-store cannot enter back/forward cache.Not actionable
Back/forward cache is disabled because some JavaScript network request received resource with Cache-Control: no-store header.Not actionable

Set an explicit width and height on image elements to reduce layout shifts and improve CLS. Learn how to set image dimensions

Why this matters

Performance issues directly impact user engagement and conversion rates.

URL
div.col > swiper-container.slide-container > swiper-slide#slide > img.w-full div.col > swiper-container.slide-container > swiper-slide#slide > img.w-full
jewishvirtuallibrary.org/_nuxt/Yemen_Jews_Rosh_Ha-Ayin-scaled.NgUQ3Vq5.jpg
div.col > swiper-container.slide-container > swiper-slide#slide > img.w-full div.col > swiper-container.slide-container > swiper-slide#slide > img.w-full
/_nuxt/Rabbi_Menachem_Mendel_Schneerson-scaled.DiWa-9HO.jpg
div.col > swiper-container.slide-container > swiper-slide#slide > img.w-full div.col > swiper-container.slide-container > swiper-slide#slide > img.w-full
/_nuxt/vecteezy_the-great-synagogue-of-budapest-hungary_1...
div.col > swiper-container.slide-container > swiper-slide#slide > img.w-full div.col > swiper-container.slide-container > swiper-slide#slide > img.w-full
/_nuxt/vecteezy_overview-of-the-western-wall-in-jerusalem...
div.col > swiper-container.slide-container > swiper-slide#slide > img.w-full div.col > swiper-container.slide-container > swiper-slide#slide > img.w-full
jewishvirtuallibrary.org/_nuxt/Iran-Jews.BhnSQeFI.jpg
div#header > div.d-flex > div.col > img.logo div#header > div.d-flex > div.col > img.logo
jewishvirtuallibrary.org/_nuxt/jvl-logo-white.BD6jMrbI.png
div.d-flex > div.d-flex > div.d-flex > img.m-2 div.d-flex > div.d-flex > div.d-flex > img.m-2
jewishvirtuallibrary.org/_nuxt/modern-jewish-history.B275WmxT.webp
div.col > swiper-container.slide-container > swiper-slide#slide > img.w-full div.col > swiper-container.slide-container > swiper-slide#slide > img.w-full
jewishvirtuallibrary.org/_nuxt/monkmap-1.BOODmNVO.png
div.col > swiper-container.slide-container > swiper-slide#slide > img.w-full div.col > swiper-container.slide-container > swiper-slide#slide > img.w-full
jewishvirtuallibrary.org/_nuxt/Palmach.Bu6Hzfl3.png
div.d-flex > div.d-flex > div.col > img.p-8 div.d-flex > div.d-flex > div.col > img.p-8
jewishvirtuallibrary.org/_nuxt/IsraelFlag.DqZRK-Do.jpeg
div.d-flex > div.d-flex > div.col > img.p-8 div.d-flex > div.d-flex > div.col > img.p-8
jewishvirtuallibrary.org/_nuxt/world-map.LtxKRr9f.jpg
div.col > swiper-container.slide-container > swiper-slide#slide > img.w-full div.col > swiper-container.slide-container > swiper-slide#slide > img.w-full
jewishvirtuallibrary.org/_nuxt/maghensyn_Lebanon.xZZoohKh.png
div.d-flex > div.d-flex > div.d-flex > img.m-2 div.d-flex > div.d-flex > div.d-flex > img.m-2
jewishvirtuallibrary.org/_nuxt/ancient-jewish-history.CH0rC6of.webp
div.d-flex > div.d-flex > div.d-flex > img.m-2 div.d-flex > div.d-flex > div.d-flex > img.m-2
jewishvirtuallibrary.org/_nuxt/history-of-jerusalem.C77BYNka.png

More information about the performance of your application. These numbers don't directly affect the Performance score.

Document request latency
Optimize DOM size
LCP breakdown
Modern HTTP
Optimize viewport for mobile
Minify CSS
Minify JavaScript
User Timing marks and measures 13 user timings
Avoid long main-thread tasks 20 long tasks found
Network Requests
Network Round Trip Times 210 ms
Server Backend Latencies 500 ms
Tasks
Diagnostics
Metrics
Screenshot Thumbnails
Final Screenshot
Script Treemap Data
Resources Summary
Avoid multiple page redirects
Initial server response time was short Root document took 550 ms
INP breakdown
Avoid non-composited animations
75

Accessibility

These checks highlight opportunities to improve the accessibility of your web app. Automatic detection can only detect a subset of issues and does not guarantee the accessibility of your web app, so manual testing is also encouraged.

Names and labels

When a button doesn't have an accessible name, screen readers announce it as "button", making it unusable for users who rely on screen readers. Learn how to make buttons more accessible.

Why this matters

Performance issues directly impact user engagement and conversion rates.

Failing Elements
div.d-flex > div.d-flex > div.d-flex > button.btn-small div.d-flex > div.d-flex > div.d-flex > button.btn-small

Informative elements should aim for short, descriptive alternate text. Decorative elements can be ignored with an empty alt attribute. Learn more about the `alt` attribute.

Why this matters

Performance issues directly impact user engagement and conversion rates.

Failing Elements
div#header > div.d-flex > div.col > img.logo div#header > div.d-flex > div.col > img.logo
div.col > swiper-container.slide-container > swiper-slide#slide > img.w-full div.col > swiper-container.slide-container > swiper-slide#slide > img.w-full
div.col > swiper-container.slide-container > swiper-slide#slide > img.w-full div.col > swiper-container.slide-container > swiper-slide#slide > img.w-full
div.col > swiper-container.slide-container > swiper-slide#slide > img.w-full div.col > swiper-container.slide-container > swiper-slide#slide > img.w-full
div.col > swiper-container.slide-container > swiper-slide#slide > img.w-full div.col > swiper-container.slide-container > swiper-slide#slide > img.w-full
div.col > swiper-container.slide-container > swiper-slide#slide > img.w-full div.col > swiper-container.slide-container > swiper-slide#slide > img.w-full
div.col > swiper-container.slide-container > swiper-slide#slide > img.w-full div.col > swiper-container.slide-container > swiper-slide#slide > img.w-full
div.col > swiper-container.slide-container > swiper-slide#slide > img.w-full div.col > swiper-container.slide-container > swiper-slide#slide > img.w-full
div.col > swiper-container.slide-container > swiper-slide#slide > img.w-full div.col > swiper-container.slide-container > swiper-slide#slide > img.w-full
swiper-slide.swiper-slide-active > a.cursor-pointer > div.border-solid > img.object-cover swiper-slide.swiper-slide-active > a.cursor-pointer > div.border-solid > img.object-cover
swiper-slide.swiper-slide-next > a.cursor-pointer > div.border-solid > img.object-cover swiper-slide.swiper-slide-next > a.cursor-pointer > div.border-solid > img.object-cover
swiper-slide > a.cursor-pointer > div.border-solid > img.object-cover swiper-slide > a.cursor-pointer > div.border-solid > img.object-cover
swiper-slide > a.cursor-pointer > div.border-solid > img.object-cover swiper-slide > a.cursor-pointer > div.border-solid > img.object-cover
swiper-slide > a.cursor-pointer > div.border-solid > img.object-cover swiper-slide > a.cursor-pointer > div.border-solid > img.object-cover
swiper-slide > a.cursor-pointer > div.border-solid > img.object-cover swiper-slide > a.cursor-pointer > div.border-solid > img.object-cover
swiper-slide > a.cursor-pointer > div.border-solid > img.object-cover swiper-slide > a.cursor-pointer > div.border-solid > img.object-cover
swiper-slide > a.cursor-pointer > div.border-solid > img.object-cover swiper-slide > a.cursor-pointer > div.border-solid > img.object-cover
swiper-slide > a.cursor-pointer > div.border-solid > img.object-cover swiper-slide > a.cursor-pointer > div.border-solid > img.object-cover
swiper-slide > a.cursor-pointer > div.border-solid > img.object-cover swiper-slide > a.cursor-pointer > div.border-solid > img.object-cover
swiper-slide > a.cursor-pointer > div.border-solid > img.object-cover swiper-slide > a.cursor-pointer > div.border-solid > img.object-cover
swiper-slide > a.cursor-pointer > div.border-solid > img.object-cover swiper-slide > a.cursor-pointer > div.border-solid > img.object-cover
swiper-slide > a.cursor-pointer > div.border-solid > img.object-cover swiper-slide > a.cursor-pointer > div.border-solid > img.object-cover
swiper-slide > a.cursor-pointer > div.border-solid > img.object-cover swiper-slide > a.cursor-pointer > div.border-solid > img.object-cover
swiper-slide > a.cursor-pointer > div.border-solid > img.object-cover swiper-slide > a.cursor-pointer > div.border-solid > img.object-cover
div.d-flex > div.d-flex > div.d-flex > img.m-2 div.d-flex > div.d-flex > div.d-flex > img.m-2
div.d-flex > div.d-flex > div.d-flex > img.m-2 div.d-flex > div.d-flex > div.d-flex > img.m-2
div.d-flex > div.d-flex > div.d-flex > img.m-2 div.d-flex > div.d-flex > div.d-flex > img.m-2
div.d-flex > div.d-flex > div.col > img.p-8 div.d-flex > div.d-flex > div.col > img.p-8
div.d-flex > div.d-flex > div.col > img.p-8 div.d-flex > div.d-flex > div.col > img.p-8

Link text (and alternate text for images, when used as links) that is discernible, unique, and focusable improves the navigation experience for screen reader users. Learn how to make links accessible.

Why this matters

Performance issues directly impact user engagement and conversion rates.

Failing Elements
div.col > div.d-flex > div.d-flex > a.router-link-active div.col > div.d-flex > div.d-flex > a.router-link-active
div.col > div.d-flex > div.d-flex > a.router-link-active div.col > div.d-flex > div.d-flex > a.router-link-active
div.col > div.d-flex > div.d-flex > a.router-link-active div.col > div.d-flex > div.d-flex > a.router-link-active
div.col > div.d-flex > div.d-flex > a.router-link-active div.col > div.d-flex > div.d-flex > a.router-link-active
div.col > div.d-flex > div.d-flex > a.router-link-active div.col > div.d-flex > div.d-flex > a.router-link-active

These are opportunities to improve the semantics of the controls in your application. This may enhance the experience for users of assistive technology, like a screen reader.

Contrast

Low-contrast text is difficult or impossible for many users to read. Learn how to provide sufficient color contrast.

Why this matters

Performance issues directly impact user engagement and conversion rates.

Failing Elements
EXPLORE div.d-flex > div.justify-content-center > div.border > span.fs-12
EXPLORE div.d-flex > div.justify-content-center > div.border > span.fs-12
EXPLORE div.d-flex > div.justify-content-center > div.border > span.fs-12

These are opportunities to improve the legibility of your content.

Internationalization and localization

If a page doesn't specify a `lang` attribute, a screen reader assumes that the page is in the default language that the user chose when setting up the screen reader. If the page isn't actually in the default language, then the screen reader might not announce the page's text correctly. Learn more about the `lang` attribute.

Why this matters

Performance issues directly impact user engagement and conversion rates.

Failing Elements
html html

These are opportunities to improve the interpretation of your content by users in different locales.

Best practices

One main landmark helps screen reader users navigate a web page. Learn more about landmarks.

Why this matters

Performance issues directly impact user engagement and conversion rates.

Failing Elements
html html

These items highlight common accessibility best practices.

Visible text labels that do not match the accessible name can result in a confusing experience for screen reader users. Learn more about accessible names.

Why this matters

Performance issues directly impact user engagement and conversion rates.

Failing Elements
Click on the Mailbox to Subscribe div#form-cr6m0ygpjo80 > div#button-wrapper-cr6m0ygpg800 > div > button#form-button-cr6m0ygpkio0
Interactive controls are keyboard focusable
Interactive elements indicate their purpose and state
The page has a logical tab order
Visual order on the page follows DOM order
User focus is not accidentally trapped in a region
The user's focus is directed to new content added to the page
HTML5 landmark elements are used to improve navigation
Offscreen content is hidden from assistive technology
Custom controls have associated labels
Custom controls have ARIA roles
`[aria-*]` attributes match their roles
`[aria-hidden="true"]` is not present on the document `<body>`
`[role]`s have all required `[aria-*]` attributes
`[role]` values are valid
`[aria-*]` attributes have valid values
`[aria-*]` attributes are valid and not misspelled
Form elements have associated labels
`[user-scalable="no"]` is not used in the `<meta name="viewport">` element and the `[maximum-scale]` attribute is not less than 5.
ARIA attributes are used as specified for the element's role
`[aria-hidden="true"]` elements do not contain focusable descendents
Elements use only permitted ARIA attributes
Document has a `<title>` element
`<frame>` or `<iframe>` elements have a title
No element has a `[tabindex]` value greater than 0
Touch targets have sufficient size and spacing.
Heading elements appear in a sequentially-descending order
Deprecated ARIA roles were not used
`[accesskey]` values are unique
`button`, `link`, and `menuitem` elements have accessible names
Elements with `role="dialog"` or `role="alertdialog"` have accessible names.
ARIA input fields have accessible names
ARIA `meter` elements have accessible names
ARIA `progressbar` elements have accessible names
Elements with an ARIA `[role]` that require children to contain a specific `[role]` have all required children.
`[role]`s are contained by their required parent element
Elements with the `role=text` attribute do not have focusable descendents.
ARIA toggle fields have accessible names
ARIA `tooltip` elements have accessible names
ARIA `treeitem` elements have accessible names
The page contains a heading, skip link, or landmark region
`<dl>`'s contain only properly-ordered `<dt>` and `<dd>` groups, `<script>`, `<template>` or `<div>` elements.
Definition list items are wrapped in `<dl>` elements
ARIA IDs are unique
No form fields have multiple labels
`<html>` element has a valid value for its `[lang]` attribute
`<html>` element has an `[xml:lang]` attribute with the same base language as the `[lang]` attribute.
Input buttons have discernible text.
`<input type="image">` elements have `[alt]` text
Links are distinguishable without relying on color.
Lists contain only `<li>` elements and script supporting elements (`<script>` and `<template>`).
List items (`<li>`) are contained within `<ul>`, `<ol>` or `<menu>` parent elements
The document does not use `<meta http-equiv="refresh">`
`<object>` elements have alternate text
Select elements have associated label elements.
Skip links are focusable.
Cells in a `<table>` element that use the `[headers]` attribute refer to table cells within the same table.
`<th>` elements and elements with `[role="columnheader"/"rowheader"]` have data cells they describe.
`[lang]` attributes have a valid value
`<video>` elements contain a `<track>` element with `[kind="captions"]`
Tables have different content in the summary attribute and `<caption>`.
All heading elements contain content.
Uses ARIA roles only on compatible elements
Image elements do not have `[alt]` attributes that are redundant text.
Identical links have the same purpose.
Tables use `<caption>` instead of cells with the `[colspan]` attribute to indicate a caption.
`<td>` elements in a large `<table>` have one or more table headers.
77

Best Practices

General

Deprecated APIs will eventually be removed from the browser. Learn more about deprecated APIs.

Why this matters

Performance issues directly impact user engagement and conversion rates.

Deprecation / WarningSource
Unload event listeners are deprecated and will be removed.
SharedStorage
StorageType.persistent is deprecated. Please use standardized navigator.storage instead.
Fledge
Topics
AttributionReporting

Errors logged to the console indicate unresolved problems. They can come from network request failures and other browser concerns. Learn more about this errors in console diagnostic audit

Why this matters

Performance issues directly impact user engagement and conversion rates.

SourceDescription
Attestation check for Protected Audience on https://a.teads.tv failed.
Attestation check for Protected Audience on https://direct.adsrvr.org failed.
Attestation check for Protected Audience on https://direct.adsrvr.org failed.
Attestation check for Protected Audience on https://fastlane.rubiconproject.com failed.
Attestation check for Protected Audience on https://fastlane.rubiconproject.com failed.
Attestation check for Protected Audience on https://hbopenbid.pubmatic.com failed.
Attestation check for Protected Audience on https://hbopenbid.pubmatic.com failed.
Attestation check for Protected Audience on https://ib.adnxs.com failed.
Attestation check for Protected Audience on https://ib.adnxs.com failed.
Attestation check for Protected Audience on https://onetag-sys.com failed.
Attestation check for Protected Audience on https://onetag-sys.com failed.
Attestation check for Protected Audience on https://prebid.a-mo.net failed.
Attestation check for Protected Audience on https://prebid.media.net failed.
Attestation check for Protected Audience on https://prebid.trustedstack.com failed.
Attestation check for Protected Audience on https://prg.smartadserver.com failed.
Attestation check for Protected Audience on https://prg.smartadserver.com failed.
Attestation check for Protected Audience on https://prg.smartadserver.com failed.
Attestation check for Protected Audience on https://targeting.unrulymedia.com failed.
Attestation check for Protected Audience on https://tlx.3lift.com failed.
Attestation check for Protected Audience on https://tlx.3lift.com failed.
Attestation check for Protected Audience on https://web.ads.aps.amazon-adsystem.com failed.
Attestation check for Protected Audience on https://web.ads.aps.amazon-adsystem.com failed.
Failed to load resource: the server responded with a status of 451 ()
Uses HTTPS
Avoids third-party cookies
Allows users to paste into input fields
Avoids requesting the geolocation permission on page load
Avoids requesting the notification permission on page load
Displays images with correct aspect ratio
Serves images with appropriate resolution
Page has the HTML doctype
Properly defines charset
No issues in the `Issues` panel in Chrome Devtools
Ensure CSP is effective against XSS attacks
Use a strong HSTS policy
Ensure proper origin isolation with COOP
Mitigate clickjacking with XFO or CSP
Mitigate DOM-based XSS with Trusted Types
Detected JavaScript libraries
Page has valid source maps
Redirects HTTP traffic to HTTPS
83

SEO

These checks ensure that your page is following basic search engine optimization advice. There are many additional factors Lighthouse does not score here that may affect your search ranking, including performance on Core Web Vitals. Learn more about Google Search Essentials.

Crawling and Indexing

Search engines may use `href` attributes on links to crawl websites. Ensure that the `href` attribute of anchor elements links to an appropriate destination, so more pages of the site can be discovered. Learn how to make links crawlable

Why this matters

Performance issues directly impact user engagement and conversion rates.

Uncrawlable Link
Library Wings div#header > div.d-flex > div.d-flex > a.position-relative
About div#header > div.d-flex > div.d-flex > a.position-relative
Bookstore div#header > div.d-flex > div.d-flex > a.position-relative
Glossary div#header > div.d-flex > div.d-flex > a.position-relative
Links div#header > div.d-flex > div.d-flex > a.position-relative
Publications div#header > div.d-flex > div.d-flex > a.position-relative
Timelines div#header > div.d-flex > div.d-flex > a.position-relative
Virtual Tours div#header > div.d-flex > div.d-flex > a.position-relative

To appear in search results, crawlers need access to your app.

Content Best Practices

Informative elements should aim for short, descriptive alternate text. Decorative elements can be ignored with an empty alt attribute. Learn more about the `alt` attribute.

Why this matters

Performance issues directly impact user engagement and conversion rates.

Failing Elements
div#header > div.d-flex > div.col > img.logo div#header > div.d-flex > div.col > img.logo
div.col > swiper-container.slide-container > swiper-slide#slide > img.w-full div.col > swiper-container.slide-container > swiper-slide#slide > img.w-full
div.col > swiper-container.slide-container > swiper-slide#slide > img.w-full div.col > swiper-container.slide-container > swiper-slide#slide > img.w-full
div.col > swiper-container.slide-container > swiper-slide#slide > img.w-full div.col > swiper-container.slide-container > swiper-slide#slide > img.w-full
div.col > swiper-container.slide-container > swiper-slide#slide > img.w-full div.col > swiper-container.slide-container > swiper-slide#slide > img.w-full
div.col > swiper-container.slide-container > swiper-slide#slide > img.w-full div.col > swiper-container.slide-container > swiper-slide#slide > img.w-full
div.col > swiper-container.slide-container > swiper-slide#slide > img.w-full div.col > swiper-container.slide-container > swiper-slide#slide > img.w-full
div.col > swiper-container.slide-container > swiper-slide#slide > img.w-full div.col > swiper-container.slide-container > swiper-slide#slide > img.w-full
div.col > swiper-container.slide-container > swiper-slide#slide > img.w-full div.col > swiper-container.slide-container > swiper-slide#slide > img.w-full
swiper-slide.swiper-slide-active > a.cursor-pointer > div.border-solid > img.object-cover swiper-slide.swiper-slide-active > a.cursor-pointer > div.border-solid > img.object-cover
swiper-slide.swiper-slide-next > a.cursor-pointer > div.border-solid > img.object-cover swiper-slide.swiper-slide-next > a.cursor-pointer > div.border-solid > img.object-cover
swiper-slide > a.cursor-pointer > div.border-solid > img.object-cover swiper-slide > a.cursor-pointer > div.border-solid > img.object-cover
swiper-slide > a.cursor-pointer > div.border-solid > img.object-cover swiper-slide > a.cursor-pointer > div.border-solid > img.object-cover
swiper-slide > a.cursor-pointer > div.border-solid > img.object-cover swiper-slide > a.cursor-pointer > div.border-solid > img.object-cover
swiper-slide > a.cursor-pointer > div.border-solid > img.object-cover swiper-slide > a.cursor-pointer > div.border-solid > img.object-cover
swiper-slide > a.cursor-pointer > div.border-solid > img.object-cover swiper-slide > a.cursor-pointer > div.border-solid > img.object-cover
swiper-slide > a.cursor-pointer > div.border-solid > img.object-cover swiper-slide > a.cursor-pointer > div.border-solid > img.object-cover
swiper-slide > a.cursor-pointer > div.border-solid > img.object-cover swiper-slide > a.cursor-pointer > div.border-solid > img.object-cover
swiper-slide > a.cursor-pointer > div.border-solid > img.object-cover swiper-slide > a.cursor-pointer > div.border-solid > img.object-cover
swiper-slide > a.cursor-pointer > div.border-solid > img.object-cover swiper-slide > a.cursor-pointer > div.border-solid > img.object-cover
swiper-slide > a.cursor-pointer > div.border-solid > img.object-cover swiper-slide > a.cursor-pointer > div.border-solid > img.object-cover
swiper-slide > a.cursor-pointer > div.border-solid > img.object-cover swiper-slide > a.cursor-pointer > div.border-solid > img.object-cover
swiper-slide > a.cursor-pointer > div.border-solid > img.object-cover swiper-slide > a.cursor-pointer > div.border-solid > img.object-cover
swiper-slide > a.cursor-pointer > div.border-solid > img.object-cover swiper-slide > a.cursor-pointer > div.border-solid > img.object-cover
div.d-flex > div.d-flex > div.d-flex > img.m-2 div.d-flex > div.d-flex > div.d-flex > img.m-2
div.d-flex > div.d-flex > div.d-flex > img.m-2 div.d-flex > div.d-flex > div.d-flex > img.m-2
div.d-flex > div.d-flex > div.d-flex > img.m-2 div.d-flex > div.d-flex > div.d-flex > img.m-2
div.d-flex > div.d-flex > div.col > img.p-8 div.d-flex > div.d-flex > div.col > img.p-8
div.d-flex > div.d-flex > div.col > img.p-8 div.d-flex > div.d-flex > div.col > img.p-8

Format your HTML in a way that enables crawlers to better understand your app’s content.

Structured data is valid
Page isn’t blocked from indexing
Document has a `<title>` element
Document has a meta description
Page has successful HTTP status code
Links have descriptive text
robots.txt is valid
Document has a valid `hreflang`
Document has a valid `rel=canonical`

Lighthouse Scores

Industry-standard audits powered by Google Lighthouse. — Desktop

55
Performance Overall performance score (0–100) based on Core Web Vitals and other metrics. 90+ is good.
79
Accessibility Measures how accessible the page is for users with disabilities. Checks color contrast, ARIA labels, and semantic HTML.
81
Best Practices Checks for modern web development best practices including HTTPS, no console errors, and secure JavaScript.
83
SEO Measures basic SEO optimizations: meta tags, crawlability, link text, and mobile friendliness.

Core Web Vitals

Key metrics that affect user experience. — Desktop

First Contentful Paint First Contentful Paint — how long until the browser renders the first piece of content. Under 1.8s is good.

1.30 s

Largest Contentful Paint Largest Contentful Paint — how long until the largest visible element loads. Under 2.5s is good.

8.44 s

Total Blocking Time Total Blocking Time — total time the main thread was blocked, preventing user input. Under 200ms is good.

161 ms

Cumulative Layout Shift Cumulative Layout Shift — measures visual stability. How much the page layout shifts during loading. Under 0.1 is good.

0.134

Speed Index Speed Index — how quickly content is visually displayed during load. Under 3.4s is good.

3.33 s

Time to Interactive Time to Interactive — how long until the page is fully interactive and responds to user input. Under 3.8s is good.

8.44 s

Detailed Report

Audit breakdown by category with detailed findings.

55

Performance

Insights

Remove large, duplicate JavaScript modules from bundles to reduce unnecessary bytes consumed by network activity.

Why this matters

Performance issues directly impact user engagement and conversion rates.

Polyfills and transforms enable older browsers to use new JavaScript features. However, many aren't necessary for modern browsers. Consider modifying your JavaScript build process to not transpile Baseline features, unless you know you must support older browsers. Learn why most sites can deploy ES6+ code without transpiling

Why this matters

Shipping ES5 transpiled code to modern browsers wastes bytes — every user with an evergreen browser pays for compatibility you don't need.

Learn more

Most users today run browsers that natively support ES6+, async/await, optional chaining, and the rest of modern JavaScript. Transpiling to ES5 'just in case' adds 20-40% to your bundle for no benefit. Configure your build to target a modern browserslist, or ship a differential bundle pair (modern + legacy) with the module/nomodule pattern.

Source: Google web.dev / Lighthouse

3rd party code can significantly impact load performance. Reduce and defer loading of 3rd party code to prioritize your page's content.

Why this matters

Performance issues directly impact user engagement and conversion rates.

Layout shifts occur when elements move absent any user interaction. Investigate the causes of layout shifts, such as elements being added, removed, or their fonts changing as the page loads.

Why this matters

Performance issues directly impact user engagement and conversion rates.

headings: [map[key:node label:Element subItemsHeading:map[key:extra] valueType:node] map[granularity:0.001 key:score label:Layout shift score subItemsHeading:map[key:cause valueType:text] valueType:numeric]]
items: [map[node:map[type:text value:Total] score:0.133716] map[node:map[boundingRect:map[bottom:2214 height:1082 left:0 right:1350 top:1132 width:1350] lhId:page-23-DIV nodeLabel:HISTORICAL TIMELINES Discover key moments in Jewish history, from ancient times… path:1,HTML,1,BODY,2,DIV,0,DIV,3,DIV,2,DIV,2,DIV selector:div > div.row > div.text-black > div.text-black snippet:<div class="text-black row d-flex py-25 px-13"> type:node] score:0.09374 subItems:map[items:[map[cause:Unsized image element extra:map[boundingRect:map[bottom:1597 height:234 left:69 right:420 top:1363 width:351] lhId:page-2-IMG nodeLabel:div.d-flex > div.d-flex > div.d-flex > img.m-2 path:1,HTML,1,BODY,2,DIV,0,DIV,3,DIV,2,DIV,2,DIV,0,DIV,0,DIV,2,DIV,2,DIV,0,DIV,1,DIV,0,DIV,0,IMG selector:div.d-flex > div.d-flex > div.d-flex > img.m-2 snippet:<img src="/_nuxt/ancient-jewish-history.CH0rC6of.webp" class="m-2" style="box-shadow:5px 5px 0px 0px #C38D00;" data-v-63a325e7=""> type:node]]] type:subitems]] map[node:map[boundingRect:map[bottom:2214 height:1082 left:0 right:1350 top:1132 width:1350] lhId:page-23-DIV nodeLabel:HISTORICAL TIMELINES Discover key moments in Jewish history, from ancient times… path:1,HTML,1,BODY,2,DIV,0,DIV,3,DIV,2,DIV,2,DIV selector:div > div.row > div.text-black > div.text-black snippet:<div class="text-black row d-flex py-25 px-13"> type:node] score:0.028952 subItems:map[items:[map[cause:Unsized image element extra:map[boundingRect:map[bottom:1597 height:234 left:69 right:420 top:1363 width:351] lhId:page-2-IMG nodeLabel:div.d-flex > div.d-flex > div.d-flex > img.m-2 path:1,HTML,1,BODY,2,DIV,0,DIV,3,DIV,2,DIV,2,DIV,0,DIV,0,DIV,2,DIV,2,DIV,0,DIV,1,DIV,0,DIV,0,IMG selector:div.d-flex > div.d-flex > div.d-flex > img.m-2 snippet:<img src="/_nuxt/ancient-jewish-history.CH0rC6of.webp" class="m-2" style="box-shadow:5px 5px 0px 0px #C38D00;" data-v-63a325e7=""> type:node]]] type:subitems]] map[node:map[boundingRect:map[bottom:2214 height:1082 left:0 right:1350 top:1132 width:1350] lhId:page-23-DIV nodeLabel:HISTORICAL TIMELINES Discover key moments in Jewish history, from ancient times… path:1,HTML,1,BODY,2,DIV,0,DIV,3,DIV,2,DIV,2,DIV selector:div > div.row > div.text-black > div.text-black snippet:<div class="text-black row d-flex py-25 px-13"> type:node] score:0.011024 subItems:map[items:[map[cause:Unsized image element extra:map[boundingRect:map[bottom:1597 height:234 left:69 right:420 top:1363 width:351] lhId:page-2-IMG nodeLabel:div.d-flex > div.d-flex > div.d-flex > img.m-2 path:1,HTML,1,BODY,2,DIV,0,DIV,3,DIV,2,DIV,2,DIV,0,DIV,0,DIV,2,DIV,2,DIV,0,DIV,1,DIV,0,DIV,0,IMG selector:div.d-flex > div.d-flex > div.d-flex > img.m-2 snippet:<img src="/_nuxt/ancient-jewish-history.CH0rC6of.webp" class="m-2" style="box-shadow:5px 5px 0px 0px #C38D00;" data-v-63a325e7=""> type:node]] map[cause:Web font extra:map[type:url value:https://jewishvirtuallibrary.org/_nuxt/Roboto-Bold._ZJd4Sbe.ttf]] map[cause:Web font extra:map[type:url value:https://jewishvirtuallibrary.org/_nuxt/Gudea-Bold.hZKtxVqa.ttf]] map[cause:Web font extra:map[type:url value:https://jewishvirtuallibrary.org/_nuxt/Roboto-Regular.CN_pkOMA.ttf]] map[cause:Web font extra:map[type:url value:https://jewishvirtuallibrary.org/_nuxt/Roboto-SemiBold.EVIM0_1H.ttf]] map[cause:Web font extra:map[type:url value:https://jewishvirtuallibrary.org/_nuxt/Gudea-Regular.DzAcgoRL.ttf]]] type:subitems]]]

Consider setting font-display to swap or optional to ensure text is consistently visible. swap can be further optimized to mitigate layout shifts with font metric overrides.

Why this matters

Performance issues directly impact user engagement and conversion rates.

A forced reflow occurs when JavaScript queries geometric properties (such as offsetWidth) after styles have been invalidated by a change to the DOM state. This can result in poor performance. Learn more about forced reflows and possible mitigations.

Why this matters

Performance issues directly impact user engagement and conversion rates.

headings: [map[key:source label:Source valueType:source-location] map[granularity:1 key:reflowTime label:Total reflow time valueType:ms]]
items: [map[reflowTime:105.722 source:map[type:text value:[unattributed]]]]

Reducing the download time of images can improve the perceived load time of the page and LCP. Learn more about optimizing image size

Why this matters

Performance issues directly impact user engagement and conversion rates.

URLResource SizeEst Savings
div.d-flex > div.d-flex > div.d-flex > img.m-2 div.d-flex > div.d-flex > div.d-flex > img.m-2
jewishvirtuallibrary.org/_nuxt/modern-jewish-history.B275WmxT.webp352.8 KiB339.1 KiB
Popup Image div > div > div#image-cr089nawhnc0 > img
/accounts/21528/uploads/pollswebinar-b22b87b59a6989e21407...202.1 KiB180.2 KiB
div.d-flex > div.d-flex > div.d-flex > img.m-2 div.d-flex > div.d-flex > div.d-flex > img.m-2
jewishvirtuallibrary.org/_nuxt/ancient-jewish-history.CH0rC6of.webp134.1 KiB120.7 KiB
swiper-slide > a.cursor-pointer > div.border-solid > img.object-cover swiper-slide > a.cursor-pointer > div.border-solid > img.object-cover
/storage/uploads/wing/11/1be41f9b-1f29-4b69-9a74-6ceb724e...110.0 KiB88.0 KiB
div.d-flex > div.d-flex > div.d-flex > img.m-2 div.d-flex > div.d-flex > div.d-flex > img.m-2
jewishvirtuallibrary.org/_nuxt/history-of-jerusalem.C77BYNka.png81.6 KiB68.0 KiB
swiper-slide > a.cursor-pointer > div.border-solid > img.object-cover swiper-slide > a.cursor-pointer > div.border-solid > img.object-cover
/storage/uploads/wing/3/6c87d582-e993-4811-9f24-1234b0b51...79.6 KiB53.4 KiB
swiper-slide.swiper-slide-active > a.cursor-pointer > div.border-solid > img.object-cover swiper-slide.swiper-slide-active > a.cursor-pointer > div.border-solid > img.object-cover
/storage/uploads/wing/1/48f62870-07ac-48fe-a253-9ee4fc3f3...74.2 KiB52.2 KiB
div.d-flex > div.d-flex > div.col > img.p-8 div.d-flex > div.d-flex > div.col > img.p-8
jewishvirtuallibrary.org/_nuxt/IsraelFlag.DqZRK-Do.jpeg63.0 KiB49.1 KiB
swiper-slide > a.cursor-pointer > div.border-solid > img.object-cover swiper-slide > a.cursor-pointer > div.border-solid > img.object-cover
/storage/uploads/wing/7/f848b9d2-13d0-4e83-a1eb-851805e8a...66.9 KiB41.3 KiB
div#header > div.px-14 > div.col > img.logo div#header > div.px-14 > div.col > img.logo
jewishvirtuallibrary.org/_nuxt/jvl-logo-white.BD6jMrbI.png40.8 KiB40.3 KiB
swiper-slide > a.cursor-pointer > div.border-solid > img.object-cover swiper-slide > a.cursor-pointer > div.border-solid > img.object-cover
/storage/uploads/wing/5/41d3ba5f-a76a-4f5a-aa24-f5568839b...60.6 KiB38.7 KiB
swiper-slide > a.cursor-pointer > div.border-solid > img.object-cover swiper-slide > a.cursor-pointer > div.border-solid > img.object-cover
/storage/uploads/wing/13/17e59cc1-7d9c-4d9f-9e90-1d843ccd...55.0 KiB36.7 KiB
swiper-slide > a.cursor-pointer > div.border-solid > img.object-cover swiper-slide > a.cursor-pointer > div.border-solid > img.object-cover
/storage/uploads/wing/12/b3f3c705-2e4e-4b0e-9ff6-a05bcc99...58.3 KiB36.4 KiB
swiper-slide > a.cursor-pointer > div.border-solid > img.object-cover swiper-slide > a.cursor-pointer > div.border-solid > img.object-cover
/storage/uploads/wing/15/50cc2757-2bcf-491f-a136-0ea1bc3b...53.3 KiB33.4 KiB
div.d-flex > div.d-flex > div.col > img.p-8 div.d-flex > div.d-flex > div.col > img.p-8
jewishvirtuallibrary.org/_nuxt/world-map.LtxKRr9f.jpg42.6 KiB33.2 KiB
swiper-slide > a.cursor-pointer > div.border-solid > img.object-cover swiper-slide > a.cursor-pointer > div.border-solid > img.object-cover
/storage/uploads/wing/10/27418e5a-1536-4f97-b368-fac9fc9d...32.1 KiB27.6 KiB
swiper-slide.swiper-slide-next > a.cursor-pointer > div.border-solid > img.object-cover swiper-slide.swiper-slide-next > a.cursor-pointer > div.border-solid > img.object-cover
/storage/uploads/wing/2/836f5307-d9ee-403c-878f-d91a63611...30.3 KiB19.9 KiB
swiper-slide > a.cursor-pointer > div.border-solid > img.object-cover swiper-slide > a.cursor-pointer > div.border-solid > img.object-cover
/storage/uploads/wing/9/53f4f324-9f62-41af-8df1-b514d5155...46.0 KiB19.9 KiB
swiper-slide > a.cursor-pointer > div.border-solid > img.object-cover swiper-slide > a.cursor-pointer > div.border-solid > img.object-cover
/storage/uploads/wing/8/ca81734c-3360-43ca-80c8-a74187507...36.1 KiB12.9 KiB
swiper-slide > a.cursor-pointer > div.border-solid > img.object-cover swiper-slide > a.cursor-pointer > div.border-solid > img.object-cover
/storage/uploads/wing/4/828ad928-ac83-4c47-a2d9-45a61c19a...26.3 KiB9.9 KiB
swiper-slide > a.cursor-pointer > div.border-solid > img.object-cover swiper-slide > a.cursor-pointer > div.border-solid > img.object-cover
/storage/uploads/wing/6/21253a63-85b7-4307-ba3b-167566e87...22.1 KiB7.9 KiB
swiper-slide > a.cursor-pointer > div.border-solid > img.object-cover swiper-slide > a.cursor-pointer > div.border-solid > img.object-cover
/storage/uploads/wing/14/85c365b9-f034-453b-977d-535b9cc6...15.7 KiB5.7 KiB

Optimize LCP by making the LCP image discoverable from the HTML immediately, and avoiding lazy-loading

Why this matters

Performance issues directly impact user engagement and conversion rates.

lhId: page-22-DIV
nodeLabel: Library Wings About Bookstore Glossary Links Publications Timelines Virtual Tou…
path: 1,HTML,1,BODY,2,DIV,0,DIV,1,DIV
selector: body > div#__nuxt > div > div#header
snippet: <div id="header" class="header bg-white text-white gap-7 row col s12 z-10" data-v-f80de7ef="">

Avoid chaining critical requests by reducing the length of chains, reducing the download size of resources, or deferring the download of unnecessary resources to improve page load.

Why this matters

Performance issues directly impact user engagement and conversion rates.

description: [preconnect](https://developer.chrome.com/docs/lighthouse/performance/uses-rel-preconnect/) hints help the browser establish a connection earlier in the page load, saving time when the first request for that origin is made. The following are the origins that the page preconnected to.
title: Preconnected origins
description: Add [preconnect](https://developer.chrome.com/docs/lighthouse/performance/uses-rel-preconnect/) hints to your most important origins, but try to use no more than 4.
title: Preconnect candidates

Requests are blocking the page's initial render, which may delay LCP. Deferring or inlining can move these network requests out of the critical path.

Why this matters

Performance issues directly impact user engagement and conversion rates.

These insights are also available in the Chrome DevTools Performance Panel - record a trace to view more detailed information.

These are the largest layout shifts observed on the page. Each table item represents a single layout shift, and shows the element that shifted the most. Below each item are possible root causes that led to the layout shift. Some of these layout shifts may not be included in the CLS metric value due to windowing. Learn how to improve CLS

Why this matters

Performance issues directly impact user engagement and conversion rates.

ElementLayout shift score
HISTORICAL TIMELINES Discover key moments in Jewish history, from ancient times… div > div.row > div.text-black > div.text-black
0.094
HISTORICAL TIMELINES Discover key moments in Jewish history, from ancient times… div > div.row > div.text-black > div.text-black
0.029
HISTORICAL TIMELINES Discover key moments in Jewish history, from ancient times… div > div.row > div.text-black > div.text-black
0.011

Time to Interactive is the amount of time it takes for the page to become fully interactive. Learn more about the Time to Interactive metric.

Why this matters

Performance issues directly impact user engagement and conversion rates.

TTI

Diagnostics

Reduce unused rules from stylesheets and defer CSS not used for above-the-fold content to decrease bytes consumed by network activity. Learn how to reduce unused CSS.

Why this matters

Performance issues directly impact user engagement and conversion rates.

Estimated savings: 100 ms 137.2 KiB

Reduce unused JavaScript and defer loading scripts until they are required to decrease bytes consumed by network activity. Learn how to reduce unused JavaScript.

Why this matters

Multi-megabyte JavaScript bundles delay every interactive feature on the page.

Learn more

This is the Lighthouse audit fired when too much JS is shipped relative to what executes. The fix isn't a config flag — it requires bundle analysis (webpack-bundle-analyzer, rollup-plugin-visualizer), splitting routes into chunks, lazy-loading off-screen components, and removing unused dependencies. Fundamentally different from minification: minifying reduces byte count, this reduces what's downloaded at all.

Source: Google web.dev / Lighthouse

Consider reducing the time spent parsing, compiling, and executing JS. You may find delivering smaller JS payloads helps with this. Learn how to reduce Javascript execution time.

Why this matters

Performance issues directly impact user engagement and conversion rates.

Consider reducing the time spent parsing, compiling and executing JS. You may find delivering smaller JS payloads helps with this. Learn how to minimize main-thread work

Why this matters

Performance issues directly impact user engagement and conversion rates.

CategoryTime Spent
Script Evaluation1.7 s
Other892 ms
Style & Layout401 ms
Script Parsing & Compilation195 ms
Rendering103 ms
Parse HTML & CSS71 ms
Garbage Collection39 ms

Many navigations are performed by going back to a previous page, or forwards again. The back/forward cache (bfcache) can speed up these return navigations. Learn more about the bfcache

Why this matters

Performance issues directly impact user engagement and conversion rates.

Failure reasonFailure type
The page has an unload handler in the main frame.Actionable
Pages with cache-control:no-store header cannot enter back/forward cache.Actionable
Pages whose main resource has cache-control:no-store cannot enter back/forward cache.Not actionable
Back/forward cache is disabled because some JavaScript network request received resource with Cache-Control: no-store header.Not actionable

Set an explicit width and height on image elements to reduce layout shifts and improve CLS. Learn how to set image dimensions

Why this matters

Performance issues directly impact user engagement and conversion rates.

URL
div.col > swiper-container.slide-container > swiper-slide#slide > img.w-full div.col > swiper-container.slide-container > swiper-slide#slide > img.w-full
jewishvirtuallibrary.org/_nuxt/Yemen_Jews_Rosh_Ha-Ayin-scaled.NgUQ3Vq5.jpg
div.col > swiper-container.slide-container > swiper-slide#slide > img.w-full div.col > swiper-container.slide-container > swiper-slide#slide > img.w-full
/_nuxt/Rabbi_Menachem_Mendel_Schneerson-scaled.DiWa-9HO.jpg
div.col > swiper-container.slide-container > swiper-slide#slide > img.w-full div.col > swiper-container.slide-container > swiper-slide#slide > img.w-full
/_nuxt/vecteezy_the-great-synagogue-of-budapest-hungary_1...
div.col > swiper-container.slide-container > swiper-slide#slide > img.w-full div.col > swiper-container.slide-container > swiper-slide#slide > img.w-full
/_nuxt/vecteezy_overview-of-the-western-wall-in-jerusalem...
div.col > swiper-container.slide-container > swiper-slide#slide > img.w-full div.col > swiper-container.slide-container > swiper-slide#slide > img.w-full
jewishvirtuallibrary.org/_nuxt/Iran-Jews.BhnSQeFI.jpg
div#header > div.px-14 > div.col > img.logo div#header > div.px-14 > div.col > img.logo
jewishvirtuallibrary.org/_nuxt/jvl-logo-white.BD6jMrbI.png
div.d-flex > div.d-flex > div.d-flex > img.m-2 div.d-flex > div.d-flex > div.d-flex > img.m-2
jewishvirtuallibrary.org/_nuxt/modern-jewish-history.B275WmxT.webp
div.col > swiper-container.slide-container > swiper-slide#slide > img.w-full div.col > swiper-container.slide-container > swiper-slide#slide > img.w-full
jewishvirtuallibrary.org/_nuxt/monkmap-1.BOODmNVO.png
div.col > swiper-container.slide-container > swiper-slide#slide > img.w-full div.col > swiper-container.slide-container > swiper-slide#slide > img.w-full
jewishvirtuallibrary.org/_nuxt/Palmach.Bu6Hzfl3.png
div.d-flex > div.d-flex > div.col > img.p-8 div.d-flex > div.d-flex > div.col > img.p-8
jewishvirtuallibrary.org/_nuxt/IsraelFlag.DqZRK-Do.jpeg
div.d-flex > div.d-flex > div.col > img.p-8 div.d-flex > div.d-flex > div.col > img.p-8
jewishvirtuallibrary.org/_nuxt/world-map.LtxKRr9f.jpg
div.col > swiper-container.slide-container > swiper-slide#slide > img.w-full div.col > swiper-container.slide-container > swiper-slide#slide > img.w-full
jewishvirtuallibrary.org/_nuxt/maghensyn_Lebanon.xZZoohKh.png
div.d-flex > div.d-flex > div.d-flex > img.m-2 div.d-flex > div.d-flex > div.d-flex > img.m-2
jewishvirtuallibrary.org/_nuxt/ancient-jewish-history.CH0rC6of.webp
div.d-flex > div.d-flex > div.d-flex > img.m-2 div.d-flex > div.d-flex > div.d-flex > img.m-2
jewishvirtuallibrary.org/_nuxt/history-of-jerusalem.C77BYNka.png

More information about the performance of your application. These numbers don't directly affect the Performance score.

Max Potential First Input Delay 110 ms
Document request latency
Optimize DOM size
LCP breakdown
Modern HTTP
Optimize viewport for mobile
Minify CSS
Minify JavaScript
Avoid long main-thread tasks 7 long tasks found
Network Requests
Network Round Trip Times 120 ms
Server Backend Latencies 200 ms
Tasks
Diagnostics
Metrics
Screenshot Thumbnails
Final Screenshot
Script Treemap Data
Resources Summary
Avoid multiple page redirects
Initial server response time was short Root document took 530 ms
INP breakdown
User Timing marks and measures
Avoid non-composited animations
79

Accessibility

These checks highlight opportunities to improve the accessibility of your web app. Automatic detection can only detect a subset of issues and does not guarantee the accessibility of your web app, so manual testing is also encouraged.

Contrast

Low-contrast text is difficult or impossible for many users to read. Learn how to provide sufficient color contrast.

Why this matters

Performance issues directly impact user engagement and conversion rates.

Failing Elements
EXPLORE div.d-flex > div.justify-content-start > div.border > span.fs-16
EXPLORE div.d-flex > div.justify-content-start > div.border > span.fs-16
EXPLORE div.d-flex > div.justify-content-start > div.border > span.fs-16

These are opportunities to improve the legibility of your content.

Internationalization and localization

If a page doesn't specify a `lang` attribute, a screen reader assumes that the page is in the default language that the user chose when setting up the screen reader. If the page isn't actually in the default language, then the screen reader might not announce the page's text correctly. Learn more about the `lang` attribute.

Why this matters

Performance issues directly impact user engagement and conversion rates.

Failing Elements
html html

These are opportunities to improve the interpretation of your content by users in different locales.

Names and labels

Informative elements should aim for short, descriptive alternate text. Decorative elements can be ignored with an empty alt attribute. Learn more about the `alt` attribute.

Why this matters

Performance issues directly impact user engagement and conversion rates.

Failing Elements
div#header > div.px-14 > div.col > img.logo div#header > div.px-14 > div.col > img.logo
div.col > swiper-container.slide-container > swiper-slide#slide > img.w-full div.col > swiper-container.slide-container > swiper-slide#slide > img.w-full
div.col > swiper-container.slide-container > swiper-slide#slide > img.w-full div.col > swiper-container.slide-container > swiper-slide#slide > img.w-full
div.col > swiper-container.slide-container > swiper-slide#slide > img.w-full div.col > swiper-container.slide-container > swiper-slide#slide > img.w-full
div.col > swiper-container.slide-container > swiper-slide#slide > img.w-full div.col > swiper-container.slide-container > swiper-slide#slide > img.w-full
div.col > swiper-container.slide-container > swiper-slide#slide > img.w-full div.col > swiper-container.slide-container > swiper-slide#slide > img.w-full
div.col > swiper-container.slide-container > swiper-slide#slide > img.w-full div.col > swiper-container.slide-container > swiper-slide#slide > img.w-full
div.col > swiper-container.slide-container > swiper-slide#slide > img.w-full div.col > swiper-container.slide-container > swiper-slide#slide > img.w-full
div.col > swiper-container.slide-container > swiper-slide#slide > img.w-full div.col > swiper-container.slide-container > swiper-slide#slide > img.w-full
swiper-slide.swiper-slide-active > a.cursor-pointer > div.border-solid > img.object-cover swiper-slide.swiper-slide-active > a.cursor-pointer > div.border-solid > img.object-cover
swiper-slide.swiper-slide-next > a.cursor-pointer > div.border-solid > img.object-cover swiper-slide.swiper-slide-next > a.cursor-pointer > div.border-solid > img.object-cover
swiper-slide > a.cursor-pointer > div.border-solid > img.object-cover swiper-slide > a.cursor-pointer > div.border-solid > img.object-cover
swiper-slide > a.cursor-pointer > div.border-solid > img.object-cover swiper-slide > a.cursor-pointer > div.border-solid > img.object-cover
swiper-slide > a.cursor-pointer > div.border-solid > img.object-cover swiper-slide > a.cursor-pointer > div.border-solid > img.object-cover
swiper-slide > a.cursor-pointer > div.border-solid > img.object-cover swiper-slide > a.cursor-pointer > div.border-solid > img.object-cover
swiper-slide > a.cursor-pointer > div.border-solid > img.object-cover swiper-slide > a.cursor-pointer > div.border-solid > img.object-cover
swiper-slide > a.cursor-pointer > div.border-solid > img.object-cover swiper-slide > a.cursor-pointer > div.border-solid > img.object-cover
swiper-slide > a.cursor-pointer > div.border-solid > img.object-cover swiper-slide > a.cursor-pointer > div.border-solid > img.object-cover
swiper-slide > a.cursor-pointer > div.border-solid > img.object-cover swiper-slide > a.cursor-pointer > div.border-solid > img.object-cover
swiper-slide > a.cursor-pointer > div.border-solid > img.object-cover swiper-slide > a.cursor-pointer > div.border-solid > img.object-cover
swiper-slide > a.cursor-pointer > div.border-solid > img.object-cover swiper-slide > a.cursor-pointer > div.border-solid > img.object-cover
swiper-slide > a.cursor-pointer > div.border-solid > img.object-cover swiper-slide > a.cursor-pointer > div.border-solid > img.object-cover
swiper-slide > a.cursor-pointer > div.border-solid > img.object-cover swiper-slide > a.cursor-pointer > div.border-solid > img.object-cover
swiper-slide > a.cursor-pointer > div.border-solid > img.object-cover swiper-slide > a.cursor-pointer > div.border-solid > img.object-cover
div.d-flex > div.d-flex > div.d-flex > img.m-2 div.d-flex > div.d-flex > div.d-flex > img.m-2
div.d-flex > div.d-flex > div.d-flex > img.m-2 div.d-flex > div.d-flex > div.d-flex > img.m-2
div.d-flex > div.d-flex > div.d-flex > img.m-2 div.d-flex > div.d-flex > div.d-flex > img.m-2
div.d-flex > div.d-flex > div.col > img.p-8 div.d-flex > div.d-flex > div.col > img.p-8
div.d-flex > div.d-flex > div.col > img.p-8 div.d-flex > div.d-flex > div.col > img.p-8

Link text (and alternate text for images, when used as links) that is discernible, unique, and focusable improves the navigation experience for screen reader users. Learn how to make links accessible.

Why this matters

Performance issues directly impact user engagement and conversion rates.

Failing Elements
div.px-14 > div.d-flex > div.d-flex > a.router-link-active div.px-14 > div.d-flex > div.d-flex > a.router-link-active
div.px-14 > div.d-flex > div.d-flex > a.router-link-active div.px-14 > div.d-flex > div.d-flex > a.router-link-active
div.px-14 > div.d-flex > div.d-flex > a.router-link-active div.px-14 > div.d-flex > div.d-flex > a.router-link-active
div.px-14 > div.d-flex > div.d-flex > a.router-link-active div.px-14 > div.d-flex > div.d-flex > a.router-link-active
div.px-14 > div.d-flex > div.d-flex > a.router-link-active div.px-14 > div.d-flex > div.d-flex > a.router-link-active
div.col > div.d-flex > div.d-flex > a.router-link-active div.col > div.d-flex > div.d-flex > a.router-link-active
div.col > div.d-flex > div.d-flex > a.router-link-active div.col > div.d-flex > div.d-flex > a.router-link-active
div.col > div.d-flex > div.d-flex > a.router-link-active div.col > div.d-flex > div.d-flex > a.router-link-active
div.col > div.d-flex > div.d-flex > a.router-link-active div.col > div.d-flex > div.d-flex > a.router-link-active
div.col > div.d-flex > div.d-flex > a.router-link-active div.col > div.d-flex > div.d-flex > a.router-link-active

These are opportunities to improve the semantics of the controls in your application. This may enhance the experience for users of assistive technology, like a screen reader.

Best practices

One main landmark helps screen reader users navigate a web page. Learn more about landmarks.

Why this matters

Performance issues directly impact user engagement and conversion rates.

Failing Elements
html html

These items highlight common accessibility best practices.

Interactive controls are keyboard focusable
Interactive elements indicate their purpose and state
The page has a logical tab order
Visual order on the page follows DOM order
User focus is not accidentally trapped in a region
The user's focus is directed to new content added to the page
HTML5 landmark elements are used to improve navigation
Offscreen content is hidden from assistive technology
Custom controls have associated labels
Custom controls have ARIA roles
`[aria-*]` attributes match their roles
`[aria-hidden="true"]` is not present on the document `<body>`
`[role]`s have all required `[aria-*]` attributes
`[role]` values are valid
`[aria-*]` attributes have valid values
`[aria-*]` attributes are valid and not misspelled
Buttons have an accessible name
Form elements have associated labels
`[user-scalable="no"]` is not used in the `<meta name="viewport">` element and the `[maximum-scale]` attribute is not less than 5.
ARIA attributes are used as specified for the element's role
`[aria-hidden="true"]` elements do not contain focusable descendents
Elements use only permitted ARIA attributes
Document has a `<title>` element
Touch targets have sufficient size and spacing.
Heading elements appear in a sequentially-descending order
Deprecated ARIA roles were not used
`[accesskey]` values are unique
`button`, `link`, and `menuitem` elements have accessible names
Elements with `role="dialog"` or `role="alertdialog"` have accessible names.
ARIA input fields have accessible names
ARIA `meter` elements have accessible names
ARIA `progressbar` elements have accessible names
Elements with an ARIA `[role]` that require children to contain a specific `[role]` have all required children.
`[role]`s are contained by their required parent element
Elements with the `role=text` attribute do not have focusable descendents.
ARIA toggle fields have accessible names
ARIA `tooltip` elements have accessible names
ARIA `treeitem` elements have accessible names
The page contains a heading, skip link, or landmark region
`<dl>`'s contain only properly-ordered `<dt>` and `<dd>` groups, `<script>`, `<template>` or `<div>` elements.
Definition list items are wrapped in `<dl>` elements
ARIA IDs are unique
No form fields have multiple labels
`<frame>` or `<iframe>` elements have a title
`<html>` element has a valid value for its `[lang]` attribute
`<html>` element has an `[xml:lang]` attribute with the same base language as the `[lang]` attribute.
Input buttons have discernible text.
`<input type="image">` elements have `[alt]` text
Links are distinguishable without relying on color.
Lists contain only `<li>` elements and script supporting elements (`<script>` and `<template>`).
List items (`<li>`) are contained within `<ul>`, `<ol>` or `<menu>` parent elements
The document does not use `<meta http-equiv="refresh">`
`<object>` elements have alternate text
Select elements have associated label elements.
Skip links are focusable.
No element has a `[tabindex]` value greater than 0
Cells in a `<table>` element that use the `[headers]` attribute refer to table cells within the same table.
`<th>` elements and elements with `[role="columnheader"/"rowheader"]` have data cells they describe.
`[lang]` attributes have a valid value
`<video>` elements contain a `<track>` element with `[kind="captions"]`
Tables have different content in the summary attribute and `<caption>`.
All heading elements contain content.
Uses ARIA roles only on compatible elements
Image elements do not have `[alt]` attributes that are redundant text.
Identical links have the same purpose.
Elements with visible text labels have matching accessible names.
Tables use `<caption>` instead of cells with the `[colspan]` attribute to indicate a caption.
`<td>` elements in a large `<table>` have one or more table headers.
81

Best Practices

General

Deprecated APIs will eventually be removed from the browser. Learn more about deprecated APIs.

Why this matters

Performance issues directly impact user engagement and conversion rates.

Deprecation / WarningSource
Unload event listeners are deprecated and will be removed.
SharedStorage
StorageType.persistent is deprecated. Please use standardized navigator.storage instead.
Fledge
Uses HTTPS
Avoids third-party cookies
Allows users to paste into input fields
Avoids requesting the geolocation permission on page load
Avoids requesting the notification permission on page load
Displays images with correct aspect ratio
Serves images with appropriate resolution
Page has the HTML doctype
Properly defines charset
No browser errors logged to the console
No issues in the `Issues` panel in Chrome Devtools
Ensure CSP is effective against XSS attacks
Use a strong HSTS policy
Ensure proper origin isolation with COOP
Mitigate clickjacking with XFO or CSP
Mitigate DOM-based XSS with Trusted Types
Detected JavaScript libraries
Page has valid source maps
Redirects HTTP traffic to HTTPS
83

SEO

These checks ensure that your page is following basic search engine optimization advice. There are many additional factors Lighthouse does not score here that may affect your search ranking, including performance on Core Web Vitals. Learn more about Google Search Essentials.

Crawling and Indexing

Search engines may use `href` attributes on links to crawl websites. Ensure that the `href` attribute of anchor elements links to an appropriate destination, so more pages of the site can be discovered. Learn how to make links crawlable

Why this matters

Performance issues directly impact user engagement and conversion rates.

Uncrawlable Link
Library Wings div#header > div.px-14 > div.d-flex > a.position-relative
About div#header > div.px-14 > div.d-flex > a.position-relative
Bookstore div#header > div.px-14 > div.d-flex > a.position-relative
Glossary div#header > div.px-14 > div.d-flex > a.position-relative
Links div#header > div.px-14 > div.d-flex > a.position-relative
Publications div#header > div.px-14 > div.d-flex > a.position-relative
Timelines div#header > div.px-14 > div.d-flex > a.position-relative
Virtual Tours div#header > div.px-14 > div.d-flex > a.position-relative

To appear in search results, crawlers need access to your app.

Content Best Practices

Informative elements should aim for short, descriptive alternate text. Decorative elements can be ignored with an empty alt attribute. Learn more about the `alt` attribute.

Why this matters

Performance issues directly impact user engagement and conversion rates.

Failing Elements
div#header > div.px-14 > div.col > img.logo div#header > div.px-14 > div.col > img.logo
div.col > swiper-container.slide-container > swiper-slide#slide > img.w-full div.col > swiper-container.slide-container > swiper-slide#slide > img.w-full
div.col > swiper-container.slide-container > swiper-slide#slide > img.w-full div.col > swiper-container.slide-container > swiper-slide#slide > img.w-full
div.col > swiper-container.slide-container > swiper-slide#slide > img.w-full div.col > swiper-container.slide-container > swiper-slide#slide > img.w-full
div.col > swiper-container.slide-container > swiper-slide#slide > img.w-full div.col > swiper-container.slide-container > swiper-slide#slide > img.w-full
div.col > swiper-container.slide-container > swiper-slide#slide > img.w-full div.col > swiper-container.slide-container > swiper-slide#slide > img.w-full
div.col > swiper-container.slide-container > swiper-slide#slide > img.w-full div.col > swiper-container.slide-container > swiper-slide#slide > img.w-full
div.col > swiper-container.slide-container > swiper-slide#slide > img.w-full div.col > swiper-container.slide-container > swiper-slide#slide > img.w-full
div.col > swiper-container.slide-container > swiper-slide#slide > img.w-full div.col > swiper-container.slide-container > swiper-slide#slide > img.w-full
swiper-slide.swiper-slide-active > a.cursor-pointer > div.border-solid > img.object-cover swiper-slide.swiper-slide-active > a.cursor-pointer > div.border-solid > img.object-cover
swiper-slide.swiper-slide-next > a.cursor-pointer > div.border-solid > img.object-cover swiper-slide.swiper-slide-next > a.cursor-pointer > div.border-solid > img.object-cover
swiper-slide > a.cursor-pointer > div.border-solid > img.object-cover swiper-slide > a.cursor-pointer > div.border-solid > img.object-cover
swiper-slide > a.cursor-pointer > div.border-solid > img.object-cover swiper-slide > a.cursor-pointer > div.border-solid > img.object-cover
swiper-slide > a.cursor-pointer > div.border-solid > img.object-cover swiper-slide > a.cursor-pointer > div.border-solid > img.object-cover
swiper-slide > a.cursor-pointer > div.border-solid > img.object-cover swiper-slide > a.cursor-pointer > div.border-solid > img.object-cover
swiper-slide > a.cursor-pointer > div.border-solid > img.object-cover swiper-slide > a.cursor-pointer > div.border-solid > img.object-cover
swiper-slide > a.cursor-pointer > div.border-solid > img.object-cover swiper-slide > a.cursor-pointer > div.border-solid > img.object-cover
swiper-slide > a.cursor-pointer > div.border-solid > img.object-cover swiper-slide > a.cursor-pointer > div.border-solid > img.object-cover
swiper-slide > a.cursor-pointer > div.border-solid > img.object-cover swiper-slide > a.cursor-pointer > div.border-solid > img.object-cover
swiper-slide > a.cursor-pointer > div.border-solid > img.object-cover swiper-slide > a.cursor-pointer > div.border-solid > img.object-cover
swiper-slide > a.cursor-pointer > div.border-solid > img.object-cover swiper-slide > a.cursor-pointer > div.border-solid > img.object-cover
swiper-slide > a.cursor-pointer > div.border-solid > img.object-cover swiper-slide > a.cursor-pointer > div.border-solid > img.object-cover
swiper-slide > a.cursor-pointer > div.border-solid > img.object-cover swiper-slide > a.cursor-pointer > div.border-solid > img.object-cover
swiper-slide > a.cursor-pointer > div.border-solid > img.object-cover swiper-slide > a.cursor-pointer > div.border-solid > img.object-cover
div.d-flex > div.d-flex > div.d-flex > img.m-2 div.d-flex > div.d-flex > div.d-flex > img.m-2
div.d-flex > div.d-flex > div.d-flex > img.m-2 div.d-flex > div.d-flex > div.d-flex > img.m-2
div.d-flex > div.d-flex > div.d-flex > img.m-2 div.d-flex > div.d-flex > div.d-flex > img.m-2
div.d-flex > div.d-flex > div.col > img.p-8 div.d-flex > div.d-flex > div.col > img.p-8
div.d-flex > div.d-flex > div.col > img.p-8 div.d-flex > div.d-flex > div.col > img.p-8

Format your HTML in a way that enables crawlers to better understand your app’s content.

Structured data is valid
Page isn’t blocked from indexing
Document has a `<title>` element
Document has a meta description
Page has successful HTTP status code
Links have descriptive text
robots.txt is valid
Document has a valid `hreflang`
Document has a valid `rel=canonical`

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