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· 0 checks — Desktop Lighthouse audit -- Performance, Accessibility, Best Practices, and SEO category breakdown.
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Detailed Report

Audit breakdown by category with detailed findings.

50

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

Performance issues directly impact user engagement and conversion rates.

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
/signals/config/154643575315468?v=2.9.298&r=stable&domain...1200.0 s126.7 KiB
connect.facebook.net/en_US/fbevents.js1200.0 s96.4 KiB
cdn.britannica.com/mendel-resources/3-180/dist/home-page.js?v=3.180.30.0 ms82.8 KiB
c.amazon-adsystem.com/aax2/apstag.js3600.0 s90.9 KiB
client.aps.amazon-adsystem.com/publisher.js3600.0 s82.4 KiB
/bDEvaLBKr59eQh0skkFpECBYKXY/gpt_and_prebid/config.js1100.0 s72.7 KiB
cdn.confiant-integrations.net/TsA7cJ0fBBXaKHjAXxO1o_FLaZc/video/config.js1100.0 s66.6 KiB
/pagead/managed/js/activeview/current/ufs_web_display.js3600.0 s73.1 KiB
jryhoywlyxnlymahs.ay.delivery/viewability/JRyhoywLYXNLYMAhs/viewability.min.js900.0 s63.3 KiB
jryhoywlyxnlymahs.ay.delivery/forest/JRyhoywLYXNLYMAhs/js/bid/forest.min.js900.0 s56.9 KiB
secure.cdn.fastclick.net/js/cnvr-coreid/latest/coreid.min.js900.0 s47.1 KiB
static.kueezrtb.com/js/latest_cls.js?_=17763618549460.0 ms37.2 KiB
jryhoywlyxnlymahs.ay.delivery/client-v2.js0.0 ms36.2 KiB
cdn.britannica.com/mendel-resources/3-180/dist/mendel-css.css?v=3.180.30.0 ms30.7 KiB
cdn.britannica.com/mendel-resources/3-180/js/libs/jquery-3.5.0.min.js?v=3.180.30.0 ms30.4 KiB
cdn.britannica.com/mendel-resources/3-180/dist/vendor-bundle.css?v=3.180.30.0 ms23.0 KiB
secure.cdn.fastclick.net/js/cnvr-launcher/latest/launcher.min.js900.0 s24.7 KiB
jryhoywlyxnlymahs.ay.delivery/thirdparty/intentiq/IIQUniversalID-6.24.js7200.0 s29.2 KiB
secure.cdn.fastclick.net/js/pubcid/latest/pubcid.min.js900.0 s21.7 KiB
b-code.liadm.com/did-0051.min.js86400.0 s45.8 KiB
ep2.adtrafficquality.google/sodar/VFc2VJAc.js3000.0 s14.4 KiB
scripts.clarity.ms/0.8.59-beta/clarity.js86400.0 s26.2 KiB
cdn.britannica.com/mendel-resources/3-180/dist/_tailwind.css?v=3.180.30.0 ms8.4 KiB
eus.rubiconproject.com/usync.js37805.0 s11.5 KiB
/mendel-resources/3-180/images/shared/britannica_black_ic...0.0 ms5.3 KiB
tags.crwdcntrl.net/lt/c/16576/sync.min.js86400.0 s13.1 KiB
/beacon.min.js/v8c78df7c7c0f484497ecbca7046644da177152312...86400.0 s10.7 KiB
a.amxrtb.com/js/cframe.js#gdpr=0&gdpr_consent=&cc=SG14400.0 s5.1 KiB
/dcdn/settings.js?a=698824&settings_type=4&ts=1776342344&...1800.0 s3.2 KiB
sb.scorecardresearch.com/internal-cs/default/beacon.js86400.0 s6.7 KiB
config.aps.amazon-adsystem.com/configs/30223600.0 s3.0 KiB
cdn.britannica.com/mendel-resources/3-180/dist/9434.965987b7.js0.0 ms2.4 KiB
cdn.britannica.com/mendel-resources/3-180/dist/home-page.css?v=3.180.30.0 ms1.8 KiB
www.britannica.com/webstats/mendelstats.js?v=10.0 ms1.8 KiB
/0ccc6fe8-1870-4ad8-b47b-6d029ac116fc/launchpad-liveramp.js0.0 ms1.8 KiB
ads.pubmatic.com/AdServer/js/userSync.js72529.0 s3.9 KiB
cdn.britannica.com/mendel-resources/3-180/dist/380.37544704.js0.0 ms1.2 KiB
cdn.britannica.com/mendel-resources/3-180/dist/380.06e77751.css0.0 ms1003 B
secure.cdn.fastclick.net/js/cnvr-launcher/latest/launcher-stub.min.js900.0 s1.1 KiB
/pagead/js/r20260415/r20110914/client/qs_click_protection...1209600.0 s8.9 KiB
/cs/usync?idmn=241&id=EtEAxgzteXTiuqonu1W9MkwDyPKxPAFjp_7...0.0 ms894 B
/cs/usync?idmn=1083&type=iframe&id=99711950-2873-53ba-bef...0.0 ms888 B
/cs/usync?idmn=109&type=iframe&id=84417c5e-1f5d-4c7f-a799...0.0 ms887 B
/cs/usync?idmn=231&type=iframe&id=42d2ee06-b215-4d96-a4dd...0.0 ms887 B
/cs/usync?idmn=869&type=iframe&id=99711950-2873-53ba-befc...0.0 ms887 B
/cs/usync?idmn=sharthrough&id=b3b7f68d-817b-48ed-b5bb-c53...0.0 ms886 B
ssp.api.tappx.com/cs/usync?idmn=45&id=4374974055011110613&gdpr=0&gdpr_consent=0.0 ms869 B
ssp.api.tappx.com/cs/usync?idmn=58&type=iframe&id=213748417047963&auxuid=0.0 ms865 B
ssp.api.tappx.com/cs/usync?idmn=82&type=iframe&id=a6c83efb8d&auxuid=0.0 ms860 B
ssp.api.tappx.com/cs/usync?idmn=999523&type=iframe&id=GDPR&auxuid=0.0 ms858 B
ssp.api.tappx.com/cs/usync?idmn=162&type=iframe&id=OPTOUT&auxuid=0.0 ms857 B
pagead2.googlesyndication.com/pagead/js/r20260415/r20110914/abg_lite_fy2021.js1209600.0 s8.4 KiB
cdn.britannica.com/mendel-resources/3-180/dist/9434.f2acc0d9.css0.0 ms564 B
/cookie?redirect_url=https%3A%2F%2Fmeasureadv.com%2FuserB...0.0 ms520 B
/api/cookie?partnerId=kueez-medinet&gdpr=&gdpr_consent=&u...0.0 ms495 B
/api/cookie?partnerId=kueez-trustedstack&userId=419363456...0.0 ms495 B
/api/cookie?partnerId=kueez-sovrn&gdpr=&gdpr_consent=&us_...0.0 ms495 B
/usersync/ogury/?cb=https%3A%2F%2Fms-cookie-sync.presage....0.0 ms405 B
/pixel/bounce/?pid=c9gd671&t=gif&uid=lfxDTmnhIYPAhy9LWtVp...0.0 ms354 B
/pagead/js/r20260415/r20110914/elements/html/omrhp_fy2021.js1209600.0 s3.3 KiB
syncingbridge.com/userBack?uid=4193634595492512000V10&p=10.0 ms240 B
syncingbridge.com/userBackIframe?uid=4193634595275677000V10&p=10.0 ms232 B
syncingbridge.com/userBackIframe?uid=4193634594229933000V10&p=40.0 ms232 B
/userBackIframe?uid=3572629698321894966&gdpr=%7BGDPR%7D&g...0.0 ms229 B
measureadv.com/userBackIframe?uid=&gdpr={GDPR}&gdpr_consent={GDPR_CONSENT}&p=90.0 ms229 B
measureadv.com/userBack?uid=OPTOUT&p=100.0 ms229 B
/ul_cb/server_match?partner_id=1805&gdpr=0&gdpr_consent=&...0.0 ms209 B
/pagead/js/r20260415/r20110914/client/window_focus_fy2021.js1209600.0 s1.3 KiB
/cm-notify?pi=ogury&gdpr=0&gdpr_consent=us_privacy=%7b%7b...0.0 ms124 B
/redir/?partnerid=76&partneruserid=&gdpr=0&gdpr_consent=&...0.0 ms113 B
/redir/?partnerid=76&partneruserid=&gdpr=0&gdpr_consent=&...0.0 ms113 B
cdn.indexww.com/ht/htw-pixel.gif?086400.0 s246 B
/v.gif?cd=0&a=698824&d=britannica.com&u=DE4F296442B511F3D...43200.0 s147 B
/cksync?cs=146&gdpr=0&gdpr_consent=&type=vid&redirect=htt...0.0 ms58 B
/api/sync?callerId=5&gdpr=1&gdpr_consent=&us_privacy={{US...0.0 ms44 B
/AdServer/ImgSync?p=162110&gdpr=&gdpr_consent=&pu=https%3...0.0 ms40 B
/AdServer/ImgSync?p=159706&gdpr=1&gdpr_consent=&us_privac...0.0 ms40 B
/AdServer/ImgSync?p=161018&gdpr=0&gdpr_consent=&pu=https%...0.0 ms40 B
/hadron.js?url=https%3A%2F%2Fwww.britannica.com%2F&ref=&_...432000.0 s186 B
/tr/?id=154643575315468&ev=PageView&dl=https%3A%2F%2Fwww....0.0 ms19 B
eus.rubiconproject.com/usync.js37805.0 s0 B
eus.rubiconproject.com/usync.js37805.0 s0 B
eus.rubiconproject.com/usync.js37805.0 s0 B
eus.rubiconproject.com/usync.js37805.0 s0 B
eus.rubiconproject.com/usync.js37805.0 s0 B
eus.rubiconproject.com/usync.js37805.0 s0 B
eus.rubiconproject.com/usync.js37805.0 s0 B
eus.rubiconproject.com/usync.js37805.0 s0 B
a.amxrtb.com/js/cframe.js#gdpr=0&gdpr_consent=&cc=SG14400.0 s0 B

Your first network request is the most important. Reduce its latency by avoiding redirects, ensuring a fast server response, and enabling text compression.

Why this matters

Performance issues directly impact user engagement and conversion rates.

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.

URLEst Savings
fonts.gstatic.com/s/materialicons/v145/flUhRq6tzZclQEJ-Vdg-IuiaDsNcIhQ8tQ.woff2110 ms

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:143.654 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.grid > div.col-sm-40 > a > img.col-70 div.grid > div.col-sm-40 > a > img.col-70
cdn.britannica.com/marketing/Premium-alldevices-white-2026.jpg312.5 KiB302.8 KiB
An image of Joy Harjo, a Native American woman, imposed on a background of a no… div.col-100 > div#vpwpl-video-player-container > div.video-container > img.rounded
cdn.britannica.com/06/269906-138-C1BB481A/interview-with-writer-joy-harjo.jpg124.2 KiB107.3 KiB
head > link head > link
s0.2mdn.net/simgad/1390025645059441743081.5 KiB70.8 KiB
The Missing Letter div.card-media > a.d-flex > div.tw:w-full > img.tw:w-full
cdn.britannica.com/kstm/GAME/missingLetter.png?w=629&h=472&c=crop40.9 KiB34.0 KiB
Mother and Young Alaska Sea Otter, Sea otter, Enhydra lutris, Prince William So… div.card-media > a.d-flex > div.tw:w-full > img.tw:w-full
/61/240861-050-F08565E4/Alaska-Sea-Otters-Enhydra-lutris-...29.4 KiB23.3 KiB
The Loop - NEW div.card-media > a.d-flex > div.tw:w-full > img.tw:w-full
cdn.britannica.com/marketing/Loop-promo-4-3.png?w=629&h=472&c=crop23.7 KiB19.7 KiB
Civil War era cannon overlooks Kennesaw Mountain National Battle. (military, ar… div.card > div.card-media > a > img.col-100
/27/273327-131-76BD5EF0/civil-war-cannon-overlooks-kenees...24.7 KiB18.6 KiB
Reunion div.card-media > a.d-flex > div.tw:w-full > img.tw:w-full
cdn.britannica.com/kstm/GAME/Reunion4-3Big.png?w=629&h=472&c=crop23.7 KiB17.0 KiB
The famous Tunnel View at Yosemite div.card > div.card-media > a > img.col-100
/52/236552-131-64AE974F/The-famous-Tunnel-View-at-Yosemit...22.3 KiB16.2 KiB
Tightrope div.card-media > a.d-flex > div.tw:w-full > img.tw:w-full
cdn.britannica.com/kstm/GAME/tightrope_promo_4_3_2x.webp?w=629&h=472&c=crop17.8 KiB14.8 KiB
Revealed div.card-media > a.d-flex > div.tw:w-full > img.tw:w-full
cdn.britannica.com/kstm/GAME/revealed-485-364-1x.png?w=629&h=472&c=crop17.1 KiB12.2 KiB
Animal-rights protest in Seoul. div.card-media > a.d-flex > div.tw:w-full > img.tw:w-full
/61/230861-050-CD2052D9/PETA-fur-protest-Myungdong-shoppi...17.7 KiB11.6 KiB
The Huajiang Canyon Bridge, the world's highest bridge with a vertical height o… div.card-media > a.d-flex > div.tw:w-full > img.tw:w-full
/07/285907-050-BDA1A788/Huajiang-Canyon-Bridge-Worlds-Hig...16.3 KiB10.2 KiB
Collage of people with financial symbols, including a large green clock, house,… div.card-media > a.d-flex > div.tw:w-full > img.tw:w-full
/07/278607-049-30717896/learning-journey-retirement-savin...16.3 KiB10.2 KiB
S&P 500 vs. Cboe Volatility Index (VIX) div.card-media > a.d-flex > div.tw:w-full > img.tw:w-full
/09/265709-050-11F07D26/vix-spikes-and-valleys-graph.jpg?...13.5 KiB7.9 KiB
Quordle div.card-media > a.d-flex > div.tw:w-full > img.tw:w-full
cdn.britannica.com/kstm/GAME/quordle.jpeg?w=629&h=472&c=crop9.2 KiB7.6 KiB
Victordle div.card-media > a.d-flex > div.tw:w-full > img.tw:w-full
cdn.britannica.com/kstm/GAME/victordle.png?w=629&h=472&c=crop9.1 KiB7.5 KiB
Civil rights leader Reverend Martin Luther King, Jr. delivers a speech to a cro… div.card > div.card-media > a > img.col-100
/32/232632-131-A2DB4925/King-Speech-at-Sproul-Plaza-in-Be...12.8 KiB7.4 KiB
Rex A. Heuermann (2nd from right, dark suit and white shirt) pleads guilty besi… div.card-media > a.d-flex > div.tw:w-full > img.tw:w-full
/81/287081-050-FC6A721B/Rex-Heuermann-pleads-guilty-to-mu...12.2 KiB7.1 KiB
Britannica Money div.grid > div.col-100 > a.gtm-money-cta-logo > img.col-65
cdn.britannica.com/money/assets/britannica-money-global-nav-logo-250x30-2x.png8.2 KiB7.0 KiB
Blossom div.card-media > a.d-flex > div.tw:w-full > img.tw:w-full
cdn.britannica.com/kstm/GAME/blossom1x.jpeg?w=629&h=472&c=crop9.4 KiB6.7 KiB
The Statue of Unity in Gujarat, India. Dedicated to Sardar Vallabhbhai Patel wh… div.card-media > a.d-flex > div.tw:w-full > img.tw:w-full
/29/240229-050-ADA5E0E5/The-Statue-of-Unity-in-Gujarat-In...10.6 KiB6.2 KiB
Child Detective in trench coat and fedora looking at large white footprints wit… div.card > div.card-media > a > img.col-100
/51/269951-131-39CF4DBC/child-detective-in-trench-coat-an...10.5 KiB6.2 KiB
Photo illustration: Tinker toys arranged in a hub div.card-media > a.d-flex > div.tw:w-full > img.tw:w-full
/39/264539-159-31C4BE40/Centralized-vs-Decentralized-Cryp...10.2 KiB6.0 KiB
Pilfer div.card-media > a.d-flex > div.tw:w-full > img.tw:w-full
cdn.britannica.com/kstm/GAME/pilfer.png?w=629&h=472&c=crop8.3 KiB6.0 KiB
American Pit Bull Terrier. div.card-media > a.d-flex > div.tw:w-full > img.tw:w-full
/11/234211-050-2D351D3C/American-pit-bull-terrier.jpg?w=4...9.8 KiB5.7 KiB
Animal dissection div.card-media > a.d-flex > div.tw:w-full > img.tw:w-full
/53/284353-050-24B40CC2/A-dead-frog-being-dissected-under...9.4 KiB5.5 KiB
Digital collage of a tiny woman stepping on a calculator key while carrying an … div.card-media > a.d-flex > div.tw:w-full > img.tw:w-full
/68/274968-159-3B823731/Inflation-Calculator-photo-illust...8.9 KiB5.2 KiB
Animal Testing div.card-media > a.d-flex > div.tw:w-full > img.tw:w-full
cdn.britannica.com/36/230836-050-DBDC2DCC/laboratory-rat.jpg?w=400&h=225&c=crop7.8 KiB4.6 KiB
Illustration of Greek god, Athena. Mythology div.card > div.card-media > a > img.col-100
/10/261010-131-7EA588C8/Greek-god-Athena-Mythology.jpg?w=...7.8 KiB4.5 KiB
Octordle div.card-media > a.d-flex > div.tw:w-full > img.tw:w-full
cdn.britannica.com/kstm/GAME/octordle-4x3.png?w=629&h=472&c=crop5.9 KiB4.2 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-31-IMG
nodeLabel: Pyramids of Giza, Cairo, Egypt (desert, pyramid, Egyptian ruins, history, histo…
path: 1,HTML,1,BODY,7,MAIN,0,DIV,0,DIV,1,DIV,5,DIV,0,DIV,1,DIV,1,DIV,0,DIV,0,DIV,0,A,0,IMG
selector: div.card > div.card-media > a.position-relative > img.w-100
snippet: <img loading="eager" src="https://cdn.britannica.com/39/155939-050-A709B5D7/Pyramids-Giza-Cairo-Egyp…" alt="Pyramids of Giza, Cairo, Egypt (desert, pyramid, Egyptian ruins, history, …" class="w-100 ">

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
value: No additional origins are good candidates for preconnecting

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.

URLTransfer SizeDuration
jryhoywlyxnlymahs.ay.delivery/manager/JRyhoywLYXNLYMAhs34.4 KiB370 ms
cdn.britannica.com/mendel-resources/3-180/dist/home-page.css?v=3.180.31.8 KiB
cdn.britannica.com/mendel-resources/3-180/dist/mendel-css.css?v=3.180.330.7 KiB123 ms
cdn.britannica.com/mendel-resources/3-180/dist/vendor-bundle.css?v=3.180.323.0 KiB123 ms
fonts.googleapis.com/icon?family=Material+Icons817 B214 ms
cdn.britannica.com/mendel-resources/3-180/dist/_tailwind.css?v=3.180.38.4 KiB249 ms

HTTP/2 and HTTP/3 offer many benefits over HTTP/1.1, such as multiplexing. Learn more about using modern HTTP.

Why this matters

Performance issues directly impact user engagement and conversion rates.

URLProtocol
/cs/usersync.php?gdpr_optin=&gdpr_consent=&us_privacy=&ty...http/1.1
/cs/usync?idmn=109&type=iframe&id=84417c5e-1f5d-4c7f-a799...http/1.1
ssp.api.tappx.com/cs/usync?idmn=162&type=iframe&id=OPTOUT&auxuid=http/1.1
/cs/usync?idmn=sharthrough&id=b3b7f68d-817b-48ed-b5bb-c53...http/1.1
/cs/usync?idmn=231&type=iframe&id=42d2ee06-b215-4d96-a4dd...http/1.1
ssp.api.tappx.com/cs/usync?idmn=82&type=iframe&id=a6c83efb8d&auxuid=http/1.1
ssp.api.tappx.com/cs/usync?idmn=13&type=iframe&id=&auxuid=http/1.1
/cs/usync?idmn=511&type=iframe&id=149c439a451840bfb658f56...http/1.1
ssp.api.tappx.com/cs/usync?idmn=999523&type=iframe&id=GDPR&auxuid=http/1.1
/cs/usync?idmn=241&id=EtEAxgzteXTiuqonu1W9MkwDyPKxPAFjp_7...http/1.1
ssp.api.tappx.com/cs/usync?idmn=45&id=4374974055011110613&gdpr=0&gdpr_consent=http/1.1
/cs/usync?idmn=31&type=iframe&id=1bddfb7e-3fbc-41c6-b837-...http/1.1
/cs/usync?idmn=1083&type=iframe&id=99711950-2873-53ba-bef...http/1.1
/cs/usync?idmn=869&type=iframe&id=99711950-2873-53ba-befc...http/1.1
ssp.api.tappx.com/cs/usync?idmn=58&type=iframe&id=213748417047963&auxuid=http/1.1

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

Redirects introduce additional delays before the page can be loaded. Learn how to avoid page redirects.

Why this matters

Performance issues directly impact user engagement and conversion rates.

Estimated savings: 957 ms
URLTime Spent
britannica.com/957 ms
www.britannica.com/0.0 ms

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.

Diagnostics

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

Performance issues directly impact user engagement and conversion rates.

Estimated savings: 40 ms 862.7 KiB
URLTransfer SizeEst Savings
/manager-script/JRyhoywLYXNLYMAhs.deploy?v=qaZ4uJbGiLe4rAGcW179.7 KiB99.4 KiB
/pagead/managed/js/gpt/m202604140101/pubads_impl.js?cb=31...187.7 KiB92.0 KiB
cdn.confiant-integrations.net/gptprebidnative/202603241056/wrap.js141.5 KiB83.3 KiB
cdn.confiant-integrations.net/video/202603241056/wrap.js125.0 KiB69.0 KiB
www.googletagmanager.com/gtag/js?id=G-TE6YF92Y0D&cx=c&gtm=4e64f0175.5 KiB67.0 KiB
www.googletagmanager.com/gtm.js?id=GTM-KRJ753NG127.1 KiB62.2 KiB
/floorPrice/v5/JRyhoywLYXNLYMAhs?t=1776361852869&d=www.br...54.8 KiB54.8 KiB
jryhoywlyxnlymahs.ay.delivery/forest/JRyhoywLYXNLYMAhs/js/bid/forest.min.js56.4 KiB52.4 KiB
www.googletagmanager.com/gtm.js?id=GTM-5W6NC8153.6 KiB50.4 KiB
cdn.britannica.com/mendel-resources/3-180/dist/home-page.js?v=3.180.382.5 KiB41.0 KiB
/ats-modules/84ec2d91-221f-4812-9e59-96237edded0f/ats.js74.6 KiB39.0 KiB
connect.facebook.net/en_US/fbevents.js96.3 KiB35.5 KiB
/signals/config/154643575315468?v=2.9.298&r=stable&domain...126.6 KiB32.0 KiB
b-code.liadm.com/did-0051.min.js45.5 KiB31.3 KiB
/floorPrice/v5/JRyhoywLYXNLYMAhs?t=1776361852869&d=www.br...54.8 KiB27.4 KiB
jryhoywlyxnlymahs.ay.delivery/manager-script/yield-manager-script-v3.11.1-prod48.5 KiB25.8 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
www.britannica.com/626 ms218 ms42 ms
Unattributable403 ms53 ms0.0 ms
jryhoywlyxnlymahs.ay.delivery/manager-script/yield-manager-script-v3.11.1-prod382 ms317 ms33 ms
cdn.confiant-integrations.net/gptprebidnative/202603241056/wrap.js283 ms218 ms38 ms
jryhoywlyxnlymahs.ay.delivery/client-v2.js200 ms186 ms4.0 ms
www.googletagmanager.com/gtm.js?id=GTM-5W6NC8198 ms164 ms19 ms
scripts.clarity.ms/0.8.59-beta/clarity.js189 ms178 ms2.8 ms
/manager-script/JRyhoywLYXNLYMAhs.deploy?v=qaZ4uJbGiLe4rAGcW183 ms153 ms20 ms
cdn.confiant-integrations.net/video/202603241056/wrap.js180 ms168 ms12 ms
/signals/config/154643575315468?v=2.9.298&r=stable&domain...163 ms123 ms22 ms
c.amazon-adsystem.com/aax2/apstag.js122 ms107 ms12 ms
www.googletagmanager.com/gtag/js?id=G-TE6YF92Y0D&cx=c&gtm=4e64f0116 ms95 ms19 ms
/pagead/managed/js/gpt/m202604140101/pubads_impl.js?cb=31...108 ms76 ms19 ms
static.kueezrtb.com/js/latest_cls.js?_=177636185494677 ms71 ms2.6 ms
www.googletagmanager.com/gtm.js?id=GTM-KRJ753NG74 ms59 ms14 ms
jryhoywlyxnlymahs.ay.delivery/thirdparty/intentiq/IIQUniversalID-6.24.js67 ms61 ms3.7 ms
cdn.britannica.com/mendel-resources/3-180/dist/home-page.js?v=3.180.362 ms50 ms9.1 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 Evaluation2.7 s
Other540 ms
Script Parsing & Compilation401 ms
Style & Layout223 ms
Garbage Collection66 ms
Rendering47 ms
Parse HTML & CSS34 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

Minifying JavaScript files can reduce payload sizes and script parse time. Learn how to minify JavaScript.

Why this matters

Performance issues directly impact user engagement and conversion rates.

Estimated savings: 0.0 ms 14.1 KiB
URLTransfer SizeEst Savings
launchpad.privacymanager.io/latest/launchpad.bundle.js45.0 KiB14.1 KiB

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: 0.0 ms 39.2 KiB
URLTransfer SizeEst Savings
cdn.britannica.com/mendel-resources/3-180/dist/vendor-bundle.css?v=3.180.322.6 KiB20.0 KiB
cdn.britannica.com/mendel-resources/3-180/dist/mendel-css.css?v=3.180.330.4 KiB19.1 KiB

Large network payloads cost users real money and are highly correlated with long load times. Learn how to reduce payload sizes.

Why this matters

Performance issues directly impact user engagement and conversion rates.

URLTransfer Size
cdn.britannica.com/marketing/Premium-alldevices-white-2026.jpg307.2 KiB
/pagead/managed/js/gpt/m202604140101/pubads_impl.js?cb=31...187.7 KiB
/manager-script/JRyhoywLYXNLYMAhs.deploy?v=qaZ4uJbGiLe4rAGcW180.2 KiB
www.googletagmanager.com/gtag/js?id=G-TE6YF92Y0D&cx=c&gtm=4e64f0175.6 KiB
www.googletagmanager.com/gtm.js?id=GTM-5W6NC8153.7 KiB
cdn.confiant-integrations.net/gptprebidnative/202603241056/wrap.js141.8 KiB
www.googletagmanager.com/gtm.js?id=GTM-KRJ753NG127.4 KiB
/signals/config/154643575315468?v=2.9.298&r=stable&domain...126.7 KiB
fonts.gstatic.com/s/materialicons/v145/flUhRq6tzZclQEJ-Vdg-IuiaDsNcIhQ8tQ.woff2125.6 KiB
cdn.confiant-integrations.net/video/202603241056/wrap.js125.4 KiB

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.grid > div.col-sm-40 > a > img.col-70 div.grid > div.col-sm-40 > a > img.col-70
cdn.britannica.com/marketing/Premium-alldevices-white-2026.jpg
Pyramids of Giza, Cairo, Egypt (desert, pyramid, Egyptian ruins, history, histo… div.card > div.card-media > a.position-relative > img.w-100
/39/155939-050-A709B5D7/Pyramids-Giza-Cairo-Egypt.jpg?w=7...
Quordle div.card-media > a.d-flex > div.tw:w-full > img.tw:w-full
cdn.britannica.com/kstm/GAME/quordle.jpeg?w=629&h=472&c=crop
The Loop - NEW div.card-media > a.d-flex > div.tw:w-full > img.tw:w-full
cdn.britannica.com/marketing/Loop-promo-4-3.png?w=629&h=472&c=crop
Tightrope div.card-media > a.d-flex > div.tw:w-full > img.tw:w-full
cdn.britannica.com/kstm/GAME/tightrope_promo_4_3_2x.webp?w=629&h=472&c=crop
The Missing Letter div.card-media > a.d-flex > div.tw:w-full > img.tw:w-full
cdn.britannica.com/kstm/GAME/missingLetter.png?w=629&h=472&c=crop
Victordle div.card-media > a.d-flex > div.tw:w-full > img.tw:w-full
cdn.britannica.com/kstm/GAME/victordle.png?w=629&h=472&c=crop
Reunion div.card-media > a.d-flex > div.tw:w-full > img.tw:w-full
cdn.britannica.com/kstm/GAME/Reunion4-3Big.png?w=629&h=472&c=crop
Revealed div.card-media > a.d-flex > div.tw:w-full > img.tw:w-full
cdn.britannica.com/kstm/GAME/revealed-485-364-1x.png?w=629&h=472&c=crop
Pilfer div.card-media > a.d-flex > div.tw:w-full > img.tw:w-full
cdn.britannica.com/kstm/GAME/pilfer.png?w=629&h=472&c=crop
Twofer Goofer div.card-media > a.d-flex > div.tw:w-full > img.tw:w-full
cdn.britannica.com/kstm/GAME/twofer-goofer.png?w=629&h=472&c=crop
Blossom div.card-media > a.d-flex > div.tw:w-full > img.tw:w-full
cdn.britannica.com/kstm/GAME/blossom1x.jpeg?w=629&h=472&c=crop
Octordle div.card-media > a.d-flex > div.tw:w-full > img.tw:w-full
cdn.britannica.com/kstm/GAME/octordle-4x3.png?w=629&h=472&c=crop
Sudoku div.card-media > a.d-flex > div.tw:w-full > img.tw:w-full
cdn.britannica.com/kstm/GAME/Sudoku.jpg?w=629&h=472&c=crop
Mother and Young Alaska Sea Otter, Sea otter, Enhydra lutris, Prince William So… div.card-media > a.d-flex > div.tw:w-full > img.tw:w-full
/61/240861-050-F08565E4/Alaska-Sea-Otters-Enhydra-lutris-...
Rex A. Heuermann (2nd from right, dark suit and white shirt) pleads guilty besi… div.card-media > a.d-flex > div.tw:w-full > img.tw:w-full
/81/287081-050-FC6A721B/Rex-Heuermann-pleads-guilty-to-mu...
The Huajiang Canyon Bridge, the world's highest bridge with a vertical height o… div.card-media > a.d-flex > div.tw:w-full > img.tw:w-full
/07/285907-050-BDA1A788/Huajiang-Canyon-Bridge-Worlds-Hig...
The Statue of Unity in Gujarat, India. Dedicated to Sardar Vallabhbhai Patel wh… div.card-media > a.d-flex > div.tw:w-full > img.tw:w-full
/29/240229-050-ADA5E0E5/The-Statue-of-Unity-in-Gujarat-In...
S&P 500 vs. Cboe Volatility Index (VIX) div.card-media > a.d-flex > div.tw:w-full > img.tw:w-full
/09/265709-050-11F07D26/vix-spikes-and-valleys-graph.jpg?...
Digital collage of a tiny woman stepping on a calculator key while carrying an … div.card-media > a.d-flex > div.tw:w-full > img.tw:w-full
/68/274968-159-3B823731/Inflation-Calculator-photo-illust...
Photo illustration: Tinker toys arranged in a hub div.card-media > a.d-flex > div.tw:w-full > img.tw:w-full
/39/264539-159-31C4BE40/Centralized-vs-Decentralized-Cryp...
Collage of people with financial symbols, including a large green clock, house,… div.card-media > a.d-flex > div.tw:w-full > img.tw:w-full
/07/278607-049-30717896/learning-journey-retirement-savin...
Animal Testing div.card-media > a.d-flex > div.tw:w-full > img.tw:w-full
cdn.britannica.com/36/230836-050-DBDC2DCC/laboratory-rat.jpg?w=400&h=225&c=crop
American Pit Bull Terrier. div.card-media > a.d-flex > div.tw:w-full > img.tw:w-full
/11/234211-050-2D351D3C/American-pit-bull-terrier.jpg?w=4...
Animal-rights protest in Seoul. div.card-media > a.d-flex > div.tw:w-full > img.tw:w-full
/61/230861-050-CD2052D9/PETA-fur-protest-Myungdong-shoppi...
Animal dissection div.card-media > a.d-flex > div.tw:w-full > img.tw:w-full
/53/284353-050-24B40CC2/A-dead-frog-being-dissected-under...
Angkor Wat, Cambodia div.card > div.card-media > a.position-relative > img.w-100
/49/94449-050-ECB0E7C2/Angkor-Wat-temple-complex-Cambodia...

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

●Layout shift culprits
●Optimize DOM size
●LCP breakdown
●Optimize viewport for mobile
●Minify CSS
●User Timing marks and measures 13 user timings
●Avoid long main-thread tasks 18 long tasks found
●Network Requests
●Network Round Trip Times 260 ms
●Server Backend Latencies 1,040 ms
●Tasks
●Diagnostics
●Metrics
●Screenshot Thumbnails
●Final Screenshot
●Script Treemap Data
●Resources Summary
●Initial server response time was short Root document took 100 ms
●Avoid large layout shifts 1 layout shift found
○INP breakdown
○Avoid non-composited animations
87

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

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.grid > div.col-sm-40 > a > img.col-70 div.grid > div.col-sm-40 > a > img.col-70

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.marketing-HOMEPAGE_BOTTOM_SUBSCRIBE2 > div.grid > div.col-sm-40 > a div.marketing-HOMEPAGE_BOTTOM_SUBSCRIBE2 > div.grid > div.col-sm-40 > a

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. Link text that is discernible improves the experience for users with low vision. Learn how to make links distinguishable.

Why this matters

Performance issues directly impact user engagement and conversion rates.

Failing Elements
archaeologists div.cards3up > div.kic-title-container > div.font-serif > a.md-crosslink
ancient Egyptian div.cards3up > div.kic-title-container > div.font-serif > a.md-crosslink
divine kingship div.cards3up > div.kic-title-container > div.font-serif > a.md-crosslink
afterlife div.cards3up > div.kic-title-container > div.font-serif > a.md-crosslink
Canada div.feature-block > div.oyr-title-container > p.font-serif > a.md-crosslink
Liberal div.feature-block > div.oyr-title-container > p.font-serif > a.md-crosslink
Mark Carney div.feature-block > div.oyr-title-container > p.font-serif > a.md-crosslink
Benin div.feature-block > div.oyr-title-container > p.font-serif > a.md-crosslink
Hungary div.kic-right-rail > div.feature-block > p.font-serif > a.md-crosslink
Viktor Orbán div.kic-right-rail > div.feature-block > p.font-serif > a.md-crosslink
Péter Magyar div.kic-right-rail > div.feature-block > p.font-serif > a.md-crosslink
European Union div.kic-right-rail > div.feature-block > p.font-serif > a.md-crosslink
Peru div.kic-right-rail > div.feature-block > p.font-serif > a.md-crosslink
Alberto Fujimori div.kic-right-rail > div.feature-block > p.font-serif > a.md-crosslink
has secured a place in the June 7 runoff div.kic-right-rail > div.feature-block > p.font-serif > a.md-crosslink
Ismail Omar Guelleh div.kic-right-rail > div.feature-block > p.font-serif > a.md-crosslink
Since he first took office in 1999 div.kic-right-rail > div.feature-block > p.font-serif > a.md-crosslink
strategic location div.kic-right-rail > div.feature-block > p.font-serif > a.md-crosslink
Indian statesman div.card > div.card-body > div.m-0 > a.md-crosslink

These are opportunities to improve the legibility of your content.

○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>`
●`[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
●Background and foreground colors have a sufficient contrast ratio
●Document has a `<title>` element
●`<frame>` or `<iframe>` elements have a title
●`<html>` element has a `[lang]` attribute
●`<html>` element has a valid value for its `[lang]` attribute
●Lists contain only `<li>` elements and script supporting elements (`<script>` and `<template>`).
●List items (`<li>`) are contained within `<ul>`, `<ol>` or `<menu>` parent elements
●No element has a `[tabindex]` value greater than 0
●Touch targets have sufficient size and spacing.
●Heading elements appear in a sequentially-descending order
●Document has a main landmark.
●Elements with visible text labels have matching accessible names.
○`[accesskey]` values are unique
○`button`, `link`, and `menuitem` elements have accessible names
○Deprecated ARIA roles were not used
○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
○`[role]`s have all required `[aria-*]` attributes
○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
○`[role]` values are valid
○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 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
○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
Topics
/manager-script/JRyhoywLYXNLYMAhs.deploy?v=qaZ4uJbGiLe4rAGcW line 11, col 83886
Unload event listeners are deprecated and will be removed.
line 1, col 194
AttributionReporting
connect.facebook.net/en_US/fbevents.js line 279, col 769

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
www.britannica.com/
Access to fetch at 'https://rp.liadm.com/j?dtstmp=1776361855327&did=did-0051&se=e30&duid=e85d52b04a00--01kpbpnnpvzzjk29s0s0cavwvk&tv=10.27.0&pu=https%3A%2F%2Fwww.britannica.com%2F&wpn=prebid&cd=.britannica.com' from origin 'https://www.britannica.com' has been blocked by CORS policy: No 'Access-Control-Allow-Origin' header is present on the requested resource.
www.britannica.com/
Access to fetch at 'https://rp.liadm.com/j?dtstmp=1776361855327&did=did-0051&se=e30&duid=e85d52b04a00--01kpbpnnpvzzjk29s0s0cavwvk&tv=10.27.0&pu=https%3A%2F%2Fwww.britannica.com%2F&wpn=prebid&cd=.britannica.com' from origin 'https://www.britannica.com' has been blocked by CORS policy: No 'Access-Control-Allow-Origin' header is present on the requested resource.
www.britannica.com/
Access to fetch at 'https://rp.liadm.com/j?dtstmp=1776361855327&did=did-0051&se=e30&duid=e85d52b04a00--01kpbpnnpvzzjk29s0s0cavwvk&tv=10.27.0&pu=https%3A%2F%2Fwww.britannica.com%2F&wpn=prebid&cd=.britannica.com' from origin 'https://www.britannica.com' has been blocked by CORS policy: No 'Access-Control-Allow-Origin' header is present on the requested resource.
www.britannica.com/
Access to fetch at 'https://rp.liadm.com/j?dtstmp=1776361855327&did=did-0051&se=e30&duid=e85d52b04a00--01kpbpnnpvzzjk29s0s0cavwvk&tv=10.27.0&pu=https%3A%2F%2Fwww.britannica.com%2F&wpn=prebid&cd=.britannica.com' from origin 'https://www.britannica.com' has been blocked by CORS policy: No 'Access-Control-Allow-Origin' header is present on the requested resource.
/j?dtstmp=1776361855327&did=did-0051&se=e30&duid=e85d52b0...
Failed to load resource: net::ERR_FAILED
/j?dtstmp=1776361855327&did=did-0051&se=e30&duid=e85d52b0...
Failed to load resource: net::ERR_FAILED
/j?dtstmp=1776361855327&did=did-0051&se=e30&duid=e85d52b0...
Failed to load resource: net::ERR_FAILED
/j?dtstmp=1776361855327&did=did-0051&se=e30&duid=e85d52b0...
Failed to load resource: net::ERR_FAILED
/FGMrCMMc/v1?gdpr=&gdpr_consent=&us_privacy=&gpp=&gpp_sid...
Failed to load resource: the server responded with a status of 422 ()
●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
92

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.

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.grid > div.col-sm-40 > a > img.col-70 div.grid > div.col-sm-40 > a > img.col-70

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
●Links are crawlable
●robots.txt is valid
●Document has a valid `hreflang`
●Document has a valid `rel=canonical`

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