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Lighthouse Mobile

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

Audit breakdown by category with detailed findings.

30

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
/stackoverflow-M6HzSe6yue/mapping.base/prebid-wrapper.js3600.0 s84.1 KiB
cdn.cookielaw.org/scripttemplates/202602.1.0/otBannerSdk.js86400.0 s129.0 KiB
superuser.com/Content/Img/favicons-sprite32.png?v=91e30776b0a0604800.0 s275.2 KiB
/stackoverflow-M6HzSe6yue/mapping.base/prebid-load.js3600.0 s16.6 KiB
superuser.com/Content/Js/full-anon.en.js?v=037e97b07fca604800.0 s128.8 KiB
superuser.com/Content/Shared/stacks.css?v=b2264ccf0463604800.0 s110.2 KiB
raven-static.aditude.io/prod/1.19.14-y0ptsc/raven.js604800.0 s107.2 KiB
cdn.cookielaw.org/scripttemplates/202602.1.0/otGPP.js86400.0 s22.2 KiB
superuser.com/cdn-cgi/challenge-platform/h/b/scripts/jsd/0b8fb825cb67/main.js?14400.0 s12.8 KiB
cdn.cookielaw.org/scripttemplates/202602.1.0/otTCF.js86400.0 s17.8 KiB
superuser.com/Content/Sites/superuser/primary.css?v=ae45545ad649604800.0 s69.6 KiB
htlbid.com/v3/mapping.base/htlbid.js?v=1.4600.0 s7.3 KiB
cdn.cookielaw.org/scripttemplates/otSDKStub.js86400.0 s9.1 KiB
superuser.com/Content/Js/webpack-chunks/svelte.en.js?v=f773033c4e0b604800.0 s32.1 KiB
/Content/Js/third-party/npm/@stackoverflow/stacks/dist/js...604800.0 s30.5 KiB
www.gravatar.com/avatar/4c5b24abfdbe0d1ba60f3c012b5f85fe?s=32&d=identicon&r=PG300.0 s3.0 KiB
raven-edge.aditude.io/raven/stackoverflow-main-I67Hg/library.js300.0 s2.6 KiB
/components/htl-injector-component.6f9fd855080891057769.js86400.0 s5.2 KiB
superuser.com/Content/Js/stub.en.js?v=e307fb81e738604800.0 s18.0 KiB
/components/creative-timed-refresh-component.a1a922b43837...86400.0 s4.2 KiB
www.gravatar.com/avatar/cb96169403450ab7cc3cb7994ed4283f?s=32&d=identicon&r=PG300.0 s1.6 KiB
superuser.com/Content/Js/webpack-chunks/stacks-svelte.en.js?v=297d3b9a88f6604800.0 s12.9 KiB
/components/htl-prebid-floors-component.d3bc1be21aeafbc98...86400.0 s3.0 KiB
/components/first-party-data-component.9031b6342187473708...86400.0 s2.9 KiB
/avatar/f5e703a0b5d5aca9eea6e22dd56c6cce?s=32&d=identicon...300.0 s1.1 KiB
/avatar/1c7750e938e081d65306db4682dd2bbc?s=32&d=identicon...300.0 s1.1 KiB
/avatar/b4903e6948943a412b3897c1739c5088?s=32&d=identicon...300.0 s1018 B
superuser.com/Content/Js/webpack-chunks/9366.en.js?v=c8d4e4e64bf3604800.0 s8.7 KiB
www.gravatar.com/avatar/a007be5a61f6aa8f3e85ae2fc18dd66e?s=32&d=identicon&r=PG300.0 s916 B
superuser.com/Content/Js/islands/signup-modal.en.js?v=f64ec881ea96604800.0 s8.4 KiB
cdn.cookielaw.org/scripttemplates/gpp.stub.js86400.0 s1.9 KiB
/components/throttle-refresh-component.de8e70e8b17a42bbf0...86400.0 s1.7 KiB
/prod/1.19.14-y0ptsc/prebid-analytics.980e6134af0dbb700d9...604800.0 s5.5 KiB
/components/refresh-all-ads-component.db7de998acab3aec35b...86400.0 s1.4 KiB
superuser.com/Content/Shared/Channels/channels.css?v=d431b1be5a03604800.0 s4.6 KiB
/components/taboola-auto-tagId-component.d35311409295ad80...86400.0 s1.1 KiB
superuser.com/px.js?ch=214400.0 s543 B
superuser.com/px.js?ch=114400.0 s369 B
superuser.com/Content/Js/google-analytics.en.js?v=48615a9a9bc4604800.0 s2.4 KiB
lh3.googleusercontent.com/a/AATXAJwrnloKlBGCT9cN6NKV8iEAKxmUyqgpNjDG9rTg=k-s3286400.0 s542 B
superuser.com/Content/Js/islands/one-tap.en.js?v=102f0378a2cf604800.0 s1.7 KiB
superuser.com/Content/Sites/superuser/Img/logo.svg?v=4bc8a703ebac604800.0 s1.4 KiB
superuser.com/Content/Js/sprinkles/left-nav-events.en.js?v=2ac13fd60bf6604800.0 s1.1 KiB
superuser.com/Content/Js/explore-qlist.en.js?v=ee2a4f8c3992604800.0 s1.0 KiB
superuser.com/Content/Js/sprinkles/cookie-consent.en.js?v=7ee6963139c5604800.0 s912 B
superuser.com/Content/Sites/superuser/Img/icon-48.png?v=9e499a07ff97604800.0 s523 B

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:49.821 source:map[type:text value:[unattributed]]] map[reflowTime:56.494 source:map[column:269884 line:1 type:source-location url:https://dn0qt3r0xannq.cloudfront.net/stackoverflow-M6HzSe6yue/mapping.base/prebid-wrapper.js urlProvider:network]]]

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
value: no origins were preconnected
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.

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#hot-network-questions > ul > li.js-hidden > div.favicon div#hot-network-questions > ul > li.js-hidden > div.favicon
superuser.com/Content/Img/favicons-sprite32.png?v=91e30776b0a0274.8 KiB200.7 KiB

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

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.

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: 1.6 s 169.5 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

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 reduce Javascript execution time.

Why this matters

Performance issues directly impact user engagement and conversion rates.

URLTotal CPU TimeScript EvaluationScript Parse
cdn.cookielaw.org/scripttemplates/202602.1.0/otGPP.js1.0 s897 ms24 ms
superuser.com/922 ms100 ms26 ms
Unattributable806 ms25 ms0.0 ms
/stackoverflow-M6HzSe6yue/mapping.base/prebid-wrapper.js680 ms385 ms48 ms
superuser.com/cdn-cgi/challenge-platform/scripts/jsd/main.js472 ms452 ms7.4 ms
www.googletagmanager.com/gtag/js?id=G-S812YQPLT2444 ms363 ms76 ms
/pagead/managed/js/gpt/m202604200101/pubads_impl.js?cb=31...376 ms268 ms103 ms
/prebid/9.30.0.js?fork=1&v=bf6611fc0393cee6578a23c9bb5689...337 ms272 ms62 ms
cdn.cookielaw.org/scripttemplates/202602.1.0/otBannerSdk.js326 ms168 ms85 ms
raven-static.aditude.io/prod/1.19.14-y0ptsc/raven.js315 ms235 ms79 ms
superuser.com/Content/Js/islands/signup-modal.en.js?v=f64ec881ea96300 ms258 ms4.5 ms
superuser.com/Content/Js/full-anon.en.js?v=037e97b07fca231 ms146 ms67 ms
/components/creative-timed-refresh-component.a1a922b43837...208 ms204 ms2.4 ms
securepubads.g.doubleclick.net/tag/js/gpt.js159 ms120 ms37 ms
superuser.com/Content/Js/stub.en.js?v=e307fb81e738148 ms92 ms7.7 ms
accounts.google.com/gsi/client139 ms71 ms66 ms
/Content/Js/third-party/npm/@stackoverflow/stacks/dist/js...135 ms113 ms18 ms
superuser.com/Content/Js/islands/one-tap.en.js?v=102f0378a2cf132 ms75 ms0.9 ms
cdn.cookielaw.org/scripttemplates/otSDKStub.js108 ms91 ms5.8 ms
ajax.googleapis.com/ajax/libs/jquery/3.7.1/jquery.min.js102 ms84 ms13 ms
/prod/1.19.14-y0ptsc/prebid-analytics.980e6134af0dbb700d9...97 ms76 ms2.8 ms
/stackoverflow-M6HzSe6yue/mapping.base/prebid-load.js96 ms86 ms7.7 ms
cdn.cookielaw.org/scripttemplates/gpp.stub.js91 ms67 ms1.5 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 Evaluation4.8 s
Style & Layout914 ms
Other897 ms
Script Parsing & Compilation840 ms
Parse HTML & CSS225 ms
Garbage Collection172 ms
Rendering85 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
Pages with WebSocket cannot enter back/forward cache.Pending browser support

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
Super User header.site-header > div.site-header--container > a.site-header--link > img.h-auto
superuser.com/Content/Sites/superuser/Img/logo.svg?v=4bc8a703ebac

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

Layout shift culprits
Document request latency
Optimize DOM size
Font display
LCP breakdown
Modern HTTP
Optimize viewport for mobile
Minify CSS
Minify JavaScript
Avoids enormous network payloads Total size was 2,007 KiB
User Timing marks and measures 5 user timings
Avoid long main-thread tasks 20 long tasks found
Network Requests
Network Round Trip Times 90 ms
Server Backend Latencies 20 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 140 ms
INP breakdown
LCP request discovery
Avoid non-composited animations
Avoid large layout shifts
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.

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
Ask Question div#mainbar > div.d-flex > div.ml12 > a.ws-nowrap
more tags div#mainbar > div.d-flex > div.flex--item > a.more-tags
Broken name resolution and connection on wireguard interface when devices are o… div#question-summary-1936943 > div.s-post-summary--content > h3.s-post-summary--content-title > a.s-link
Mihir div.s-user-card--info > div.s-user-card--link > a.flex--item > span
8k div#question-summary-1128864 > div.s-post-summary--stats > div.s-post-summary--stats-item > span.s-post-summary--stats-item-number
views div#question-summary-1128864 > div.s-post-summary--stats > div.s-post-summary--stats-item > span.s-post-summary--stats-item-unit
Automated PuTTY session load and commands div#question-summary-1128864 > div.s-post-summary--content > h3.s-post-summary--content-title > a.s-link
Community div.s-user-card--info > div.s-user-card--link > a.flex--item > span
4k div#question-summary-334139 > div.s-post-summary--stats > div.s-post-summary--stats-item > span.s-post-summary--stats-item-number
views div#question-summary-334139 > div.s-post-summary--stats > div.s-post-summary--stats-item > span.s-post-summary--stats-item-unit
Executable does not exist in /usr/local/bin, but it does in /usr/bin, yet it st… div#question-summary-334139 > div.s-post-summary--content > h3.s-post-summary--content-title > a.s-link
Community div.s-user-card--info > div.s-user-card--link > a.flex--item > span
How to set an alias in Windows Command Line? div#question-summary-560519 > div.s-post-summary--content > h3.s-post-summary--content-title > a.s-link
Qwerty div.s-user-card--info > div.s-user-card--link > a.flex--item > span
Windows batch files: popd returns 0 error code but still triggers || conditiona… div#question-summary-1936942 > div.s-post-summary--content > h3.s-post-summary--content-title > a.s-link
Regus Pregus div.s-user-card--info > div.s-user-card--link > a.flex--item > span
How do I preview a camera in Microsoft Teams? div#question-summary-1936916 > div.s-post-summary--content > h3.s-post-summary--content-title > a.s-link
Manngo div.s-user-card--info > div.s-user-card--link > a.flex--item > span
How do you find out the version number of Microsoft Publisher by clicking butto… div#question-summary-1936902 > div.s-post-summary--content > h3.s-post-summary--content-title > a.s-link
cachius div.s-user-card--info > div.s-user-card--link > a.flex--item > span
33k div#question-summary-926077 > div.s-post-summary--stats > div.s-post-summary--stats-item > span.s-post-summary--stats-item-number
views div#question-summary-926077 > div.s-post-summary--stats > div.s-post-summary--stats-item > span.s-post-summary--stats-item-unit
Remove entry from Microsoft Word Navigation Pane div#question-summary-926077 > div.s-post-summary--content > h3.s-post-summary--content-title > a.s-link
AJM div.s-user-card--info > div.s-user-card--link > a.flex--item > span
7k div#question-summary-1491600 > div.s-post-summary--stats > div.s-post-summary--stats-item > span.s-post-summary--stats-item-number
views div#question-summary-1491600 > div.s-post-summary--stats > div.s-post-summary--stats-item > span.s-post-summary--stats-item-unit
How can I set my preferred game controller through the registry? div#question-summary-1491600 > div.s-post-summary--content > h3.s-post-summary--content-title > a.s-link
Community div.s-user-card--info > div.s-user-card--link > a.flex--item > span
8k div#question-summary-1004515 > div.s-post-summary--stats > div.s-post-summary--stats-item > span.s-post-summary--stats-item-number
views div#question-summary-1004515 > div.s-post-summary--stats > div.s-post-summary--stats-item > span.s-post-summary--stats-item-unit
how to fix unknown directive error in nginx? div#question-summary-1004515 > div.s-post-summary--content > h3.s-post-summary--content-title > a.s-link
Community div.s-user-card--info > div.s-user-card--link > a.flex--item > span
9k div#question-summary-1485706 > div.s-post-summary--stats > div.s-post-summary--stats-item > span.s-post-summary--stats-item-number
views div#question-summary-1485706 > div.s-post-summary--stats > div.s-post-summary--stats-item > span.s-post-summary--stats-item-unit
How to delete Search History in Outlook 2016 div#question-summary-1485706 > div.s-post-summary--content > h3.s-post-summary--content-title > a.s-link
AJM div.s-user-card--info > div.s-user-card--link > a.flex--item > span
1k div#question-summary-1718873 > div.s-post-summary--stats > div.s-post-summary--stats-item > span.s-post-summary--stats-item-number
views div#question-summary-1718873 > div.s-post-summary--stats > div.s-post-summary--stats-item > span.s-post-summary--stats-item-unit
Windows Unable to delete file with reserved name div#question-summary-1718873 > div.s-post-summary--content > h3.s-post-summary--content-title > a.s-link
AJM div.s-user-card--info > div.s-user-card--link > a.flex--item > span
10k div#question-summary-725630 > div.s-post-summary--stats > div.s-post-summary--stats-item > span.s-post-summary--stats-item-number
views div#question-summary-725630 > div.s-post-summary--stats > div.s-post-summary--stats-item > span.s-post-summary--stats-item-unit
Where can I find the xmodemsend command in TeraTerm? div#question-summary-725630 > div.s-post-summary--content > h3.s-post-summary--content-title > a.s-link
Fady GG div.s-user-card--info > div.s-user-card--link > a.flex--item > span
1k div#question-summary-1186984 > div.s-post-summary--stats > div.s-post-summary--stats-item > span.s-post-summary--stats-item-number
views div#question-summary-1186984 > div.s-post-summary--stats > div.s-post-summary--stats-item > span.s-post-summary--stats-item-unit
Combine multiple ifs in bash div#question-summary-1186984 > div.s-post-summary--content > h3.s-post-summary--content-title > a.s-link
Kamil Maciorowski div.s-user-card--info > div.s-user-card--link > a.flex--item > span
Browse more Questions div#content > div.inner-content > div#mainbar > a.s-btn
Numerical iterative solution of a self-consistent non-linear integral equation div#hot-network-questions > ul > li > a.js-gps-track
If I throw a dildo during a basketball game to win a Kalshi bet, am I guilty of… div#hot-network-questions > ul > li > a.js-gps-track
What did Jesus mean by we will do greater things than he did div#hot-network-questions > ul > li > a.js-gps-track
How do I preview a camera in Microsoft Teams? div#hot-network-questions > ul > li > a.js-gps-track
Intro to Smooth Manifolds by Lee, Problem 6-13c div#hot-network-questions > ul > li > a.js-gps-track
80’s sci-fi show where the main character is picking up random stuff from trash… div#hot-network-questions > ul > li > a.js-gps-track
Strange bracket matching problem in exam class with the use of `\half` command div#hot-network-questions > ul > li > a.js-gps-track
How to get the timestamp of an electronic signature in PDF? div#hot-network-questions > ul > li > a.js-gps-track
Op-amp LED driver: residual current at Vin = 0 V div#hot-network-questions > ul > li > a.js-gps-track
How can I easily get an approximate measurement for the soil bearing strength w… div#hot-network-questions > ul > li > a.js-gps-track
An editor told to resubmit my journal paper as a new submission; I did and a di… div#hot-network-questions > ul > li > a.js-gps-track
HTTP 400 "Bad Request" - how may I diagnose this from server side? div#hot-network-questions > ul > li > a.js-gps-track
Story of planet where people telepathically know others' needs, show up where n… div#hot-network-questions > ul > li.js-hidden > a.js-gps-track
Isn't the voltage divider on the right equivalent of the one on the left? div#hot-network-questions > ul > li.js-hidden > a.js-gps-track
LibreOffice added blue dots and a "Responsible" field on each page after saving… div#hot-network-questions > ul > li.js-hidden > a.js-gps-track
Why does a mixed regression model return only one of two highly correlated vari… div#hot-network-questions > ul > li.js-hidden > a.js-gps-track
Why present perfect simple but not continuous? div#hot-network-questions > ul > li.js-hidden > a.js-gps-track
Why is "cross" used for stage movements in scripts? div#hot-network-questions > ul > li.js-hidden > a.js-gps-track
How should I contextualise group theory results? div#hot-network-questions > ul > li.js-hidden > a.js-gps-track
What are the impacts of a homebrew feature allowing Ready as a bonus action? div#hot-network-questions > ul > li.js-hidden > a.js-gps-track
Determining a quadrilateral up to similarity with four angles div#hot-network-questions > ul > li.js-hidden > a.js-gps-track
How do believers in ontological randomness explain why the universe follows sta… div#hot-network-questions > ul > li.js-hidden > a.js-gps-track
Be troubled with div#hot-network-questions > ul > li.js-hidden > a.js-gps-track
KVM bridged networking with a single network adapter and external DHCP? div#hot-network-questions > ul > li.js-hidden > a.js-gps-track
Recent questions feed div.inner-content > div#sidebar > div#feed-link > a
SUPER USER nav.site-footer--nav > div.site-footer--col > h5.-title > a
COMPANY nav.site-footer--nav > div.site-footer--col > h5.-title > a.js-gps-track
STACK EXCHANGE NETWORK div.site-footer--col > div > h5.-title > a
Site design / logo © 2026 Stack Exchange Inc; div.site-footer--container > div.site-footer--copyright > p.md:mb0 > span
user contributions licensed under div.site-footer--container > div.site-footer--copyright > p.md:mb0 > span
rev 2026.4.21.42306 div.site-footer--container > div.site-footer--copyright > p.md:mb0 > span#svnrev

These are opportunities to improve the legibility of your content.

Navigation

Properly ordered headings that do not skip levels convey the semantic structure of the page, making it easier to navigate and understand when using assistive technologies. Learn more about heading order.

Why this matters

Performance issues directly impact user engagement and conversion rates.

Failing Elements
Broken name resolution and connection on wireguard interface when devices are o… div > div#question-summary-1936943 > div.s-post-summary--content > h3.s-post-summary--content-title

These are opportunities to improve keyboard navigation in your application.

Names and labels

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
body.home-page > header.s-topbar > div.s-topbar--container > a.s-topbar--menu-btn body.home-page > header.s-topbar > div.s-topbar--container > a.s-topbar--menu-btn
body.home-page > header.s-topbar > div.s-topbar--container > a.s-topbar--logo body.home-page > header.s-topbar > div.s-topbar--container > a.s-topbar--logo

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

Touch targets with sufficient size and spacing help users who may have difficulty targeting small controls to activate the targets. Learn more about touch targets.

Why this matters

Performance issues directly impact user engagement and conversion rates.

Failing Elements
Technology div > ul.-list > li > a.-link
Business div > ul.-list > li > a.-link

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
Image elements have `[alt]` attributes
`[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
Elements with `role="dialog"` or `role="alertdialog"` have accessible names.
`[aria-hidden="true"]` elements do not contain focusable descendents
Elements use only permitted ARIA attributes
Document has a `<title>` element
`<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
Document has a main landmark.
Deprecated ARIA roles were not used
Uses ARIA roles only on compatible elements
Identical links have the same purpose.
Elements with visible text labels have matching accessible names.
`[accesskey]` values are unique
`button`, `link`, and `menuitem` elements 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 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
Form elements have associated labels
Links are distinguishable without relying on color.
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.
Image elements do not have `[alt]` attributes that are redundant text.
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.
73

Best Practices

User Experience

Image natural dimensions should be proportional to the display size and the pixel ratio to maximize image clarity. Learn how to provide responsive images.

Why this matters

Performance issues directly impact user engagement and conversion rates.

URLDisplayed sizeActual sizeExpected size
site logo div.s-modal--dialog > h1#signup-modal-title > div.s-modal--header > img.h48
superuser.com/Content/Sites/superuser/Img/icon-48.png?v=9e499a07ff9748 x 4848 x 4872 x 72

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
SharedStorage
StorageType.persistent is deprecated. Please use standardized navigator.storage instead.
Fledge

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
Not signed in with the identity provider.
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
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 DOM-based XSS with Trusted Types
Detected JavaScript libraries
Page has valid source maps
Redirects HTTP traffic to HTTPS
Mitigate clickjacking with XFO or CSP
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

Descriptive link text helps search engines understand your content. Learn how to make links more accessible.

Why this matters

Performance issues directly impact user engagement and conversion rates.

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 are crawlable
Image elements have `[alt]` attributes
Document has a valid `hreflang`
Document has a valid `rel=canonical`
robots.txt is valid

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