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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.

86

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
/wp-content/uploads/2022/12/EPFL-vue-aerienne-Jamani-Cail...0.0 ms348.3 KiB
actu.epfl.ch/image/163596/1440x810.jpg0.0 ms312.4 KiB
www.epfl.ch/wp-includes/js/jquery/jquery.js?ver=3.7.10.0 ms84.6 KiB
/wp-content/themes/wp-theme-2018/assets/js/vendors.min.js...0.0 ms80.2 KiB
www.epfl.ch/wp-content/uploads/2026/04/Anna-Fontcuberta-i-Morral-768x432.jpg0.0 ms58.9 KiB
/wp-content/themes/wp-theme-2018/assets/css/elements.min....0.0 ms52.4 KiB
www.epfl.ch/wp-content/uploads/2026/03/dimensions-num20-flipbook-768x432.jpg0.0 ms50.8 KiB
www.epfl.ch/wp-content/uploads/2026/04/David-Atienza-768x432.jpg0.0 ms38.7 KiB
memento.epfl.ch/image/32970/509x286.jpg900.0 s38.8 KiB
memento.epfl.ch/image/32754/509x286.jpg900.0 s36.3 KiB
memento.epfl.ch/image/32144/509x286.jpg900.0 s31.4 KiB
memento.epfl.ch/image/32730/509x286.jpg900.0 s31.1 KiB
memento.epfl.ch/image/32071/509x286.jpg900.0 s28.8 KiB
/wp-content/themes/wp-theme-2018/assets/js/elements.min.j...0.0 ms21.2 KiB
www.epfl.ch/fonts/SuisseIntl-SemiBold-WebS.woff20.0 ms18.3 KiB
www.epfl.ch/fonts/SuisseIntl-Regular-WebS.woff20.0 ms17.9 KiB
www.epfl.ch/wp-includes/js/jquery/jquery-migrate.js?ver=3.4.10.0 ms11.2 KiB
/wp-content/plugins/enlighter/cache/enlighterjs.min.css?v...0.0 ms10.1 KiB
www.epfl.ch/wp-includes/js/twemoji.js?ver=6.9.40.0 ms9.8 KiB
/wp-content/themes/wp-theme-2018/assets/css/vendors.min.c...0.0 ms7.7 KiB
/wp-content/plugins/wp-gutenberg-epfl/frontend/lib/list.m...0.0 ms7.2 KiB
www.epfl.ch/wp-content/uploads/2021/09/Recherche.png0.0 ms6.0 KiB
www.epfl.ch/wp-content/uploads/2021/09/Facultes.png0.0 ms4.7 KiB
www.epfl.ch/wp-content/uploads/2021/09/Education.png0.0 ms4.7 KiB
www.epfl.ch/wp-content/uploads/2021/09/Innovation.png0.0 ms4.6 KiB
www.epfl.ch/wp-includes/js/wp-emoji.js?ver=6.9.40.0 ms4.4 KiB
/wp-content/plugins/flowpaper-lite-pdf-flipbook/assets/li...0.0 ms3.9 KiB
www.epfl.ch/wp-content/uploads/2021/09/Campus.png0.0 ms3.8 KiB
/wp-content/plugins/wp-gutenberg-epfl/build/style-index.c...0.0 ms2.1 KiB
www.epfl.ch/wp-content/themes/wp-theme-2018/theme/style.min.css?ver=17763805260.0 ms2.0 KiB
www.epfl.ch/wp-content/uploads/2025/03/EPFL-logo.png0.0 ms1.9 KiB
www.epfl.ch/wp-content/themes/wp-theme-2018/assets/svg/epfl-logo.svg0.0 ms1.6 KiB
www.epfl.ch/wp-content/themes/wp-theme-2018/style.css?ver=17763805260.0 ms1.4 KiB

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.

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:2.121 source:map[column:197 line:724 type:source-location url:https://www.googletagmanager.com/gtm.js?id=GTM-PJGBG5R 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:84.131 source:map[type:text value:[unattributed]]] map[reflowTime:2.121 source:map[column:376 line:697 type:source-location url:https://www.googletagmanager.com/gtm.js?id=GTM-PJGBG5R 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
A eukaryotic cell with the centrioles shown in yellow. © iStock div.list-group > div.fullwidth-teaser > picture > img
actu.epfl.ch/image/163596/1440x810.jpg311.9 KiB141.9 KiB
Vue aérienne de l'EPFL © Jamani Caillet / EPFL, 2022 div.container-full > div.fullwidth-teaser > figure.cover > img
/wp-content/uploads/2022/12/EPFL-vue-aerienne-Jamani-Cail...347.2 KiB140.1 KiB
Portrait d'Anna Fontcuverta i Morral - 2026 EPFL/Mediacom - CC-BY-SA 4.0 div.card > a.card-img-top > picture > img.img-fluid
www.epfl.ch/wp-content/uploads/2026/04/Anna-Fontcuberta-i-Morral-768x432.jpg57.8 KiB41.5 KiB
div.list-group-teaser-container > div.list-group-teaser-thumbnail > picture.card-img-top > img.img-fluid div.list-group-teaser-container > div.list-group-teaser-thumbnail > picture.card-img-top > img.img-fluid
memento.epfl.ch/image/32970/509x286.jpg38.5 KiB36.1 KiB
Couverture du numéro 20 du magazine Dimensions. Un enfant sur un tricycle trave… div.card > a.card-img-top > picture > img.img-fluid
www.epfl.ch/wp-content/uploads/2026/03/dimensions-num20-flipbook-768x432.jpg49.7 KiB34.8 KiB
div.list-group-teaser-container > div.list-group-teaser-thumbnail > picture.card-img-top > img.img-fluid div.list-group-teaser-container > div.list-group-teaser-thumbnail > picture.card-img-top > img.img-fluid
memento.epfl.ch/image/32754/509x286.jpg36.0 KiB33.6 KiB
Finale suisse MT180. Graphisme: Laura Persat div.list-group-teaser-container > div.list-group-teaser-thumbnail > picture.card-img-top > img.img-fluid
memento.epfl.ch/image/32730/509x286.jpg30.8 KiB28.5 KiB
portrait de David Atienza - 2026 EPFL CC BY SA div.card > a.card-img-top > picture > img.img-fluid
www.epfl.ch/wp-content/uploads/2026/04/David-Atienza-768x432.jpg37.7 KiB26.3 KiB
div.list-group-teaser-container > div.list-group-teaser-thumbnail > picture.card-img-top > img.img-fluid div.list-group-teaser-container > div.list-group-teaser-thumbnail > picture.card-img-top > img.img-fluid
memento.epfl.ch/image/32071/509x286.jpg28.5 KiB26.1 KiB
Ig Nobel a.card > div.card-body > picture.card-img-top > img.img-fluid
memento.epfl.ch/image/32144/509x286.jpg31.1 KiB7.5 KiB
An atom div.card-header > div.row > div.col-md-6 > img
www.epfl.ch/wp-content/uploads/2021/09/Recherche.png5.0 KiB4.1 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-0-IMG
nodeLabel: A eukaryotic cell with the centrioles shown in yellow. © iStock
path: 1,HTML,1,BODY,1,DIV,7,DIV,0,DIV,2,DIV,0,MAIN,0,ARTICLE,0,DIV,3,DIV,0,DIV,0,DIV,0,PICTURE,5,IMG
selector: div.list-group > div.fullwidth-teaser > picture > img
snippet: <img decoding="async" src="https://actu.epfl.ch/image/163596/1440x810.jpg" aria-labelledby="background-label" alt="A eukaryotic cell with the centrioles shown in yellow. © iStock">

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
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
www.epfl.ch/wp-includes/js/jquery/jquery.js?ver=3.7.184.6 KiB160 ms
www.epfl.ch/wp-includes/js/jquery/jquery-migrate.js?ver=3.4.111.2 KiB
cdnjs.cloudflare.com/ajax/libs/jquery/3.7.1/jquery.min.js?ver=177638052627.5 KiB284 ms
/wp-content/plugins/wp-gutenberg-epfl/frontend/lib/list.m...7.2 KiB
/wp-content/themes/wp-theme-2018/assets/css/elements.min....52.4 KiB
/wp-content/themes/wp-theme-2018/assets/css/vendors.min.c...7.7 KiB
/wp-content/plugins/enlighter/cache/enlighterjs.min.css?v...10.1 KiB
www.epfl.ch/wp-content/themes/wp-theme-2018/theme/style.min.css?ver=17763805262.0 KiB
/wp-content/plugins/wp-gutenberg-epfl/build/style-index.c...2.1 KiB
/wp-content/plugins/flowpaper-lite-pdf-flipbook/assets/li...3.9 KiB
www.epfl.ch/wp-content/themes/wp-theme-2018/style.css?ver=17763805261.4 KiB

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
www.epfl.ch/fonts/SuisseIntl-Regular-WebS.woff220 ms
www.epfl.ch/fonts/SuisseIntl-SemiBold-WebS.woff220 ms

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

Diagnostics

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: 40 ms 50.5 KiB
URLTransfer SizeEst Savings
www.epfl.ch/wp-includes/js/jquery/jquery.js?ver=3.7.183.5 KiB42.7 KiB
www.epfl.ch/wp-includes/js/jquery/jquery-migrate.js?ver=3.4.110.2 KiB4.2 KiB
www.epfl.ch/wp-includes/js/twemoji.js?ver=6.9.48.8 KiB3.7 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: 40 ms 46.7 KiB
URLTransfer SizeEst Savings
/wp-content/themes/wp-theme-2018/assets/css/elements.min....51.4 KiB46.7 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.

Estimated savings: 130 ms 248.5 KiB
URLTransfer SizeEst Savings
www.googletagmanager.com/gtm.js?id=GTM-PJGBG5R135.0 KiB65.0 KiB
/wp-content/themes/wp-theme-2018/assets/js/vendors.min.js...79.0 KiB64.5 KiB
www.googletagmanager.com/gtag/js?id=G-N6BF9H5G73&cx=c&gtm=4e64h1149.1 KiB63.4 KiB
www.epfl.ch/wp-includes/js/jquery/jquery.js?ver=3.7.183.5 KiB55.6 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
Ig Nobel a.card > div.card-body > picture.card-img-top > img.img-fluid
memento.epfl.ch/image/32144/509x286.jpg
div.list-group-teaser-container > div.list-group-teaser-thumbnail > picture.card-img-top > img.img-fluid div.list-group-teaser-container > div.list-group-teaser-thumbnail > picture.card-img-top > img.img-fluid
memento.epfl.ch/image/32754/509x286.jpg
div.list-group-teaser-container > div.list-group-teaser-thumbnail > picture.card-img-top > img.img-fluid div.list-group-teaser-container > div.list-group-teaser-thumbnail > picture.card-img-top > img.img-fluid
memento.epfl.ch/image/32071/509x286.jpg
Finale suisse MT180. Graphisme: Laura Persat div.list-group-teaser-container > div.list-group-teaser-thumbnail > picture.card-img-top > img.img-fluid
memento.epfl.ch/image/32730/509x286.jpg
div.list-group-teaser-container > div.list-group-teaser-thumbnail > picture.card-img-top > img.img-fluid div.list-group-teaser-container > div.list-group-teaser-thumbnail > picture.card-img-top > img.img-fluid
memento.epfl.ch/image/32970/509x286.jpg
Logo EPFL, École polytechnique fédérale de Lausanne div#page > header.header > a.logo > img.img-fluid
www.epfl.ch/wp-content/themes/wp-theme-2018/assets/svg/epfl-logo.svg
Logo of the EPFL div.card-header > div.row > div.col-md-6 > img
www.epfl.ch/wp-content/uploads/2025/03/EPFL-logo.png
Schools and Colleges div.card-header > div.row > div.col-md-6 > img
www.epfl.ch/wp-content/uploads/2021/09/Facultes.png
Rolex Learning Center div.card-header > div.row > div.col-md-6 > img
www.epfl.ch/wp-content/uploads/2021/09/Campus.png
A person reading a book div.card-header > div.row > div.col-md-6 > img
www.epfl.ch/wp-content/uploads/2021/09/Education.png
An atom div.card-header > div.row > div.col-md-6 > img
www.epfl.ch/wp-content/uploads/2021/09/Recherche.png
A rocket div.card-header > div.row > div.col-md-6 > img
www.epfl.ch/wp-content/uploads/2021/09/Innovation.png

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

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: 892 ms
URLTime Spent
epfl.ch/665 ms
www.epfl.ch/227 ms
www.epfl.ch/en/0.0 ms
●Time to Interactive 2.3 s
●Max Potential First Input Delay 80 ms
●Layout shift culprits
●Optimize DOM size
●LCP breakdown
●Modern HTTP
●Optimize viewport for mobile
●Minify CSS
●Avoids enormous network payloads Total size was 1,751 KiB
●User Timing marks and measures 5 user timings
●JavaScript execution time 0.2 s
●Minimizes main-thread work 0.7 s
●Avoid long main-thread tasks 1 long task found
●Page didn't prevent back/forward cache restoration
●Network Requests
●Network Round Trip Times 150 ms
●Server Backend Latencies 190 ms
●Tasks
●Diagnostics
●Metrics
●Screenshot Thumbnails
●Final Screenshot
●Script Treemap Data
●Resources Summary
●Initial server response time was short Root document took 30 ms
●Avoid large layout shifts 1 layout shift found
○INP breakdown
○Avoid non-composited animations
93

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
Read more sur Tech Transfer. div.fullwidth-teaser > div.fullwidth-teaser-text > div.fullwidth-teaser-header > a.btn
23.04.2026 a.card > div.card-body > div.card-info > span.card-info-date
18:00 a.card > div.card-body > div.card-info > span.event-time
20:00 a.card > div.card-body > div.card-info > span.event-time
Maps and directions div.fullwidth-teaser > div.fullwidth-teaser-text > div.fullwidth-teaser-header > a.btn
About div.footer-group > div.footer-sitemap-col > button.footer-title > strong
Organization and identity div#collapse-footer-1 > ul.footer-links > li > a
Associated Campuses div#collapse-footer-1 > ul.footer-links > li > a
Data div#collapse-footer-1 > ul.footer-links > li > a
Presidency div#collapse-footer-1 > ul.footer-links > li > a
Vice Presidencies div#collapse-footer-1 > ul.footer-links > li > a
Working at EPFL div#collapse-footer-1 > ul.footer-links > li > a
Recruiting EPFL Talents div#collapse-footer-1 > ul.footer-links > li > a
Equality, Diversity, Inclusion div#collapse-footer-1 > ul.footer-links > li > a
Respect div#collapse-footer-1 > ul.footer-links > li > a
Sustainability div#collapse-footer-1 > ul.footer-links > li > a
News & Media div#collapse-footer-1 > ul.footer-links > li > a
Philanthropy div#collapse-footer-1 > ul.footer-links > li > a
EPFL Alumni div#collapse-footer-1 > ul.footer-links > li > a
Education div.footer-group > div.footer-sitemap-col > button.footer-title > strong
Admission div#collapse-footer-2 > ul.footer-links > li > a
Academic Calendar div#collapse-footer-2 > ul.footer-links > li > a
Preparatory Year (CMS) div#collapse-footer-2 > ul.footer-links > li > a
Bachelor div#collapse-footer-2 > ul.footer-links > li > a
Master div#collapse-footer-2 > ul.footer-links > li > a
Doctorate div#collapse-footer-2 > ul.footer-links > li > a
SHS Program div#collapse-footer-2 > ul.footer-links > li > a
Continuing Education - Extension School div#collapse-footer-2 > ul.footer-links > li > a
Study Management div#collapse-footer-2 > ul.footer-links > li > a
International div#collapse-footer-2 > ul.footer-links > li > a
Teaching div#collapse-footer-2 > ul.footer-links > li > a
Educational Initiatives div#collapse-footer-2 > ul.footer-links > li > a
Education & Science Outreach div#collapse-footer-2 > ul.footer-links > li > a
Infrastructures Under Development div#collapse-footer-2 > ul.footer-links > li > a
Engaging with Society div#collapse-footer-2 > ul.footer-links > li > a
Research div.footer-group > div.footer-sitemap-col > button.footer-title > strong
Mission and Policy div#collapse-footer-3 > ul.footer-links > li > a
Research Domains div#collapse-footer-3 > ul.footer-links > li > a
EPFL Research Facilities div#collapse-footer-3 > ul.footer-links > li > a
Faculty Members div#collapse-footer-3 > ul.footer-links > li > a
Solutions 4 Sustainability - S4S div#collapse-footer-3 > ul.footer-links > li > a
Awards and Prizes div#collapse-footer-3 > ul.footer-links > li > a
Funding Opportunities div#collapse-footer-3 > ul.footer-links > li > a
Research Management Support div#collapse-footer-3 > ul.footer-links > li > a
From Lab to Market div#collapse-footer-3 > ul.footer-links > li > a
Research Ethics div#collapse-footer-3 > ul.footer-links > li > a
Research with Animals div#collapse-footer-3 > ul.footer-links > li > a
Open Science div#collapse-footer-3 > ul.footer-links > li > a
Innovation div.footer-group > div.footer-sitemap-col > button.footer-title > strong
Industry Collaboration div#collapse-footer-4 > ul.footer-links > li > a
Innovation Initiatives div#collapse-footer-4 > ul.footer-links > li > a
Startup Launchpad div#collapse-footer-4 > ul.footer-links > li > a
Campus div.footer-group > div.footer-sitemap-col > button.footer-title > strong
Services & Resources div#collapse-footer-5 > ul.footer-links > li > a
Library div#collapse-footer-5 > ul.footer-links > li > a
Restaurants, Shops & Hotels div#collapse-footer-5 > ul.footer-links > li > a
Security, Prevention & Health div#collapse-footer-5 > ul.footer-links > li > a
Sports div#collapse-footer-5 > ul.footer-links > li > a
Community & Support div#collapse-footer-5 > ul.footer-links > li > a
Chaplaincy div#collapse-footer-5 > ul.footer-links > li > a
Events div#collapse-footer-5 > ul.footer-links > li > a
Arts & Culture div#collapse-footer-5 > ul.footer-links > li > a
Associations div#collapse-footer-5 > ul.footer-links > li > a
Visit EPFL div#collapse-footer-5 > ul.footer-links > li > a
Mobility & Travel div#collapse-footer-5 > ul.footer-links > li > a
Schools & Colleges footer.footer > div.footer-group > div.footer-faculties > button.footer-title
School of Architecture, Civil & Environmental Engineering ENAC div#collapse-fac > ul.footer-links > li > a
ENAC ul.footer-links > li > a > strong
School of Basic Sciences SB div#collapse-fac > ul.footer-links > li > a
SB ul.footer-links > li > a > strong
School of Engineering STI div#collapse-fac > ul.footer-links > li > a
STI ul.footer-links > li > a > strong
School of Computer & Communication Sciences IC div#collapse-fac > ul.footer-links > li > a
IC ul.footer-links > li > a > strong
School of Life Sciences SV div#collapse-fac > ul.footer-links > li > a
SV ul.footer-links > li > a > strong
College of Management of Technology CDM div#collapse-fac > ul.footer-links > li > a
CDM ul.footer-links > li > a > strong
Practical div.container > footer.footer > div.footer-group > p.footer-title
Follow EPFL on social media div.container > footer.footer > div.footer-group > p.footer-title
Accessibility footer.footer > div.footer-legal > div.footer-legal-links > a
Disclaimer footer.footer > div.footer-legal > div.footer-legal-links > a
Privacy policy footer.footer > div.footer-legal > div.footer-legal-links > a
© 2025 EPFL, all rights reserved footer.footer > div.footer-legal > div > p

These are opportunities to improve the legibility of your content.

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
div#page > header.header > div.dropdown > a.dropdown-toggle div#page > header.header > div.dropdown > a.dropdown-toggle

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.

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
Read more sur Tech Transfer. div.fullwidth-teaser > div.fullwidth-teaser-text > div.fullwidth-teaser-header > a.btn
Maps and directions div.fullwidth-teaser > div.fullwidth-teaser-text > div.fullwidth-teaser-header > a.btn
○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.
●`button`, `link`, and `menuitem` elements have accessible names
●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
●Touch targets have sufficient size and spacing.
●Heading elements appear in a sequentially-descending order
●Document has a main landmark.
●Deprecated ARIA roles were not used
●Identical links have the same purpose.
○`[accesskey]` values are unique
○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.
○Uses ARIA roles only on compatible elements
○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.
96

Best Practices

General

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.epfl.ch/en/
The Content-Security-Policy directive 'worker-src' contains the keyword 'none' alongside with other source expressions. The keyword 'none' must be the only source expression in the directive value, otherwise it is ignored.
www.epfl.ch/en/
The Content-Security-Policy directive 'worker-src' contains the keyword 'none' alongside with other source expressions. The keyword 'none' must be the only source expression in the directive value, otherwise it is ignored.
www.epfl.ch/en/
The Content-Security-Policy directive 'worker-src' contains the keyword 'none' alongside with other source expressions. The keyword 'none' must be the only source expression in the directive value, otherwise it is ignored.
●Uses HTTPS
●Avoids deprecated APIs
●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 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
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.

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.

Link destinationLink Text
actu.epfl.ch/news/lighting-up-the-organizers-of-the-cell-s-architectRead more
www.epfl.ch/innovation/Read more

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

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
EN nav.nav-lang > ul.dropdown-menu > li > a.active

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

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

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