Lighthouse Mobile

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

SCORE

GRADE

FIX

REVIEW

PASS

INFO

Detailed Report

Audit breakdown by category with detailed findings.

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.

Request	Cache TTL	Transfer Size
/sites/default/files/styles/16_9_lg_792x446/public/2025-0...	1209600.0 s	433.1 KiB
/sites/default/files/styles/16_9_md_588x330/public/2026-0...	1209600.0 s	369.2 KiB
/sites/default/files/css/css_vbH7SZFOKmi1Jt4GAldwamrVpI7P...	86400.0 s	90.1 KiB
/sites/default/files/styles/16_9_md_588x330/public/2026-0...	1209600.0 s	221.8 KiB
/sites/default/files/css/css_fF_ngLVO43l3-9cUNiTNUuZLglxo...	86400.0 s	50.0 KiB
/sites/default/files/styles/16_9_md_588x330/public/2022-1...	1209600.0 s	189.4 KiB
/sites/default/files/styles/16_9_md_588x330/public/2020-0...	1209600.0 s	165.6 KiB
/cdn-cgi/challenge-platform/h/b/scripts/jsd/625261456364/...	14400.0 s	11.5 KiB
/sites/default/files/js/js_tzoLcjdeSzPZwn63KF-tyOCA_bDWuZ...	1209600.0 s	48.9 KiB
www.education.gouv.fr/libraries/dsfr/dist/fonts/Marianne-Regular_Italic.woff2	1209600.0 s	43.4 KiB
www.education.gouv.fr/libraries/dsfr/dist/fonts/Marianne-Bold.woff2	1209600.0 s	41.2 KiB
www.education.gouv.fr/libraries/dsfr/dist/fonts/Marianne-Medium.woff2	1209600.0 s	41.1 KiB
www.education.gouv.fr/libraries/dsfr/dist/fonts/Marianne-Regular.woff2	1209600.0 s	40.5 KiB
/sites/default/files/js/js_WfPPp7sH-1ECmhNZVUIC56qjeFlH4G...	1209600.0 s	39.1 KiB
www.education.gouv.fr/libraries/dsfr/dist/dsfr.module.js?v=1.x	1209600.0 s	36.8 KiB
/libraries/tarteaucitron.js/tarteaucitron.services.js?v=2...	1209600.0 s	32.7 KiB
www.education.gouv.fr/libraries/dsfr/dist/analytics/analytics.module.js?td4vez	1209600.0 s	22.1 KiB
/sites/default/files/css/css_n2--NQYMQlobwzlsubBx59EyImce...	86400.0 s	5.0 KiB
/libraries/tarteaucitron.js/css/tarteaucitron.css?v=20220322	1209600.0 s	4.5 KiB
www.education.gouv.fr/core/assets/vendor/modernizr/modernizr.min.js?v=3.11.7	1209600.0 s	3.1 KiB
www.education.gouv.fr/sites/default/files/2025-11/calendar-svg-474095.svg	1209600.0 s	1.9 KiB
/sites/default/files/css/css_lFJuqrBJuPD967tnROjsQvtwzw9b...	1209600.0 s	1.9 KiB
/libraries/tarteaucitron.js/lang/tarteaucitron.fr.js?v=20...	1209600.0 s	1.5 KiB
www.education.gouv.fr/libraries/dsfr/dist/icons/logo/bluesky-fill.svg	1209600.0 s	562 B
www.education.gouv.fr/libraries/dsfr/dist/icons/logo/instagram-fill.svg	1209600.0 s	560 B
www.education.gouv.fr/libraries/dsfr/dist/icons/logo/youtube-fill.svg	1209600.0 s	524 B
www.education.gouv.fr/libraries/dsfr/dist/icons/logo/linkedin-box-fill.svg	1209600.0 s	484 B
www.education.gouv.fr/libraries/dsfr/dist/icons/logo/fr--tiktok-fill.svg	1209600.0 s	450 B
www.education.gouv.fr/libraries/dsfr/dist/icons/logo/twitter-x-fill.svg	1209600.0 s	418 B
www.education.gouv.fr/libraries/dsfr/dist/icons/logo/facebook-circle-fill.svg	1209600.0 s	364 B
www.education.gouv.fr/libraries/dsfr/dist/icons/system/search-line.svg	1209600.0 s	358 B
www.education.gouv.fr/libraries/dsfr/dist/icons/system/menu-fill.svg	1209600.0 s	322 B
www.education.gouv.fr/libraries/dsfr/dist/icons/system/external-link-line.svg	1209600.0 s	306 B
www.education.gouv.fr/libraries/dsfr/dist/icons/system/close-line.svg	1209600.0 s	286 B
www.education.gouv.fr/libraries/dsfr/dist/icons/arrows/arrow-right-line.svg	1209600.0 s	268 B
www.education.gouv.fr/libraries/dsfr/dist/icons/arrows/arrow-down-s-line.svg	1209600.0 s	260 B
/sites/default/files/css/css_N5EDBe35cbGk77JW3v0FfHnN-fcH...	1209600.0 s	231 B

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: Neutre 1

path: 1,HTML,1,BODY,0,DIV,0,DIV,2,MAIN,1,DIV,0,DIV,0,DIV,0,DIV,0,ARTICLE,0,DIV,0,DIV,0,DIV,0,ARTICLE,0,DIV,0,DIV,0,DIV,0,DIV,1,FIGURE,0,DIV,0,DIV,0,IMG

selector: figure.fr-hero-home__media > div.fr-hero-home__img > div.fr-ratio-16x9 > img.fr-responsive-img

snippet: <img loading="lazy" src="/sites/default/files/styles/16_9_lg_792x446/public/2025-04/neutre-1-467526…" width="792" height="446" alt="Neutre 1" typeof="foaf:Image" class="fr-responsive-img" data-fr-js-ratio="true">

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.

URL	Transfer Size	Duration
/sites/default/files/js/js_tzoLcjdeSzPZwn63KF-tyOCA_bDWuZ...	48.9 KiB	150 ms
/sites/default/files/js/js_WfPPp7sH-1ECmhNZVUIC56qjeFlH4G...	39.1 KiB	300 ms
/sites/default/files/css/css_fF_ngLVO43l3-9cUNiTNUuZLglxo...	50.0 KiB	150 ms
/sites/default/files/css/css_vbH7SZFOKmi1Jt4GAldwamrVpI7P...	90.1 KiB	600 ms
www.education.gouv.fr/core/assets/vendor/modernizr/modernizr.min.js?v=3.11.7	3.1 KiB
/sites/default/files/css/css_n2--NQYMQlobwzlsubBx59EyImce...	5.0 KiB

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.

	URL	Resource Size	Est Savings
Neutre 1 `figure.fr-hero-home__media > div.fr-hero-home__img > div.fr-ratio-16x9 > img.fr-responsive-img`	/sites/default/files/styles/16_9_lg_792x446/public/2025-0...	432.5 KiB	420.3 KiB
div.fr-card__header > div.fr-card__img > div.fr-responsive-img > img.fr-responsive-img `div.fr-card__header > div.fr-card__img > div.fr-responsive-img > img.fr-responsive-img`	/sites/default/files/styles/16_9_md_588x330/public/2026-0...	368.6 KiB	354.4 KiB
div.fr-card__header > div.fr-card__img > div.fr-responsive-img > img.fr-responsive-img `div.fr-card__header > div.fr-card__img > div.fr-responsive-img > img.fr-responsive-img`	/sites/default/files/styles/16_9_md_588x330/public/2026-0...	221.4 KiB	207.2 KiB
div.fr-card__header > div.fr-card__img > div.fr-responsive-img > img.fr-responsive-img `div.fr-card__header > div.fr-card__img > div.fr-responsive-img > img.fr-responsive-img`	/sites/default/files/styles/16_9_md_588x330/public/2022-1...	188.9 KiB	174.7 KiB
div.fr-card__header > div.fr-card__img > div.fr-responsive-img > img.fr-responsive-img `div.fr-card__header > div.fr-card__img > div.fr-responsive-img > img.fr-responsive-img`	/sites/default/files/styles/16_9_md_588x330/public/2020-0...	165.3 KiB	151.0 KiB

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

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

Why this matters

Performance issues directly impact user engagement and conversion rates.

TTI

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

Why this matters

Performance issues directly impact user engagement and conversion rates.

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: 390 ms 22.7 KiB

URL	Transfer Size	Est Savings
/libraries/tarteaucitron.js/tarteaucitron.services.js?v=2...	32.5 KiB	9.2 KiB
www.education.gouv.fr/libraries/dsfr/dist/dsfr.module.js?v=1.x	36.6 KiB	8.1 KiB
www.education.gouv.fr/libraries/dsfr/dist/analytics/analytics.module.js?td4vez	22.0 KiB	5.3 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: 750 ms 126.7 KiB

URL	Transfer Size	Est Savings
/sites/default/files/css/css_vbH7SZFOKmi1Jt4GAldwamrVpI7P...	90.0 KiB	77.2 KiB
/sites/default/files/css/css_fF_ngLVO43l3-9cUNiTNUuZLglxo...	50.0 KiB	49.5 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.

Estimated savings: 870 ms 75.5 KiB

URL	Transfer Size	Est Savings
/sites/default/files/js/js_tzoLcjdeSzPZwn63KF-tyOCA_bDWuZ...	48.8 KiB	29.7 KiB
/libraries/tarteaucitron.js/tarteaucitron.services.js?v=2...	32.5 KiB	23.6 KiB
/sites/default/files/js/js_WfPPp7sH-1ECmhNZVUIC56qjeFlH4G...	39.0 KiB	22.2 KiB

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.

Category	Time Spent
Other	934 ms
Script Evaluation	921 ms
Style & Layout	613 ms
Parse HTML & CSS	107 ms
Script Parsing & Compilation	78 ms
Rendering	45 ms

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.fr-tile > div.fr-tile__header > div.fr-tile__pictogram > img.no-image-style `div.fr-tile > div.fr-tile__header > div.fr-tile__pictogram > img.no-image-style`	www.education.gouv.fr/sites/default/files/2025-11/calendar-svg-474095.svg
div.fr-tile > div.fr-tile__header > div.fr-tile__pictogram > img.no-image-style `div.fr-tile > div.fr-tile__header > div.fr-tile__pictogram > img.no-image-style`
div.fr-tile > div.fr-tile__header > div.fr-tile__pictogram > img.no-image-style `div.fr-tile > div.fr-tile__header > div.fr-tile__pictogram > img.no-image-style`
div.fr-tile > div.fr-tile__header > div.fr-tile__pictogram > img.no-image-style `div.fr-tile > div.fr-tile__header > div.fr-tile__pictogram > img.no-image-style`
div.fr-tile > div.fr-tile__header > div.fr-tile__pictogram > img.no-image-style `div.fr-tile > div.fr-tile__header > div.fr-tile__pictogram > img.no-image-style`
div.fr-tile > div.fr-tile__header > div.fr-tile__pictogram > img.no-image-style `div.fr-tile > div.fr-tile__header > div.fr-tile__pictogram > img.no-image-style`

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

●Forced reflow

●LCP breakdown

●Modern HTTP

●Optimize viewport for mobile

●Minify CSS

●Avoids enormous network payloads Total size was 1,938 KiB

●JavaScript execution time 0.9 s

●Avoid long main-thread tasks 9 long tasks found

●Page didn't prevent back/forward cache restoration

●Network Requests

●Network Round Trip Times 20 ms

●Server Backend Latencies 30 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 40 ms

○INP breakdown

○User Timing marks and measures

○Avoid non-composited animations

○Avoid large layout shifts

100

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.

○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

●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

●`[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

●`[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

●`<html>` element has a `[lang]` attribute

●`<html>` element has a valid value for its `[lang]` attribute

●Links are distinguishable without relying on color.

●Links have a discernible name

●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.

●`[lang]` attributes have a valid value

●Heading elements appear in a sequentially-descending order

●Skip links are focusable.

●Document has a main landmark.

●Deprecated ARIA roles were not used

●Elements with visible text labels have matching accessible names.

○`[accesskey]` values are unique

○`button`, `link`, and `menuitem` elements have accessible names

○Elements with `role="dialog"` or `role="alertdialog"` have accessible names.

○ARIA input fields have accessible names

○ARIA `meter` elements have accessible names

○ARIA `progressbar` elements have accessible names

○Elements with 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

○The document does not use `<meta http-equiv="refresh">`

○`<object>` elements have alternate text

○Select elements have associated label elements.

○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.

○`<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.

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 / Warning	Source
SharedStorage	www.education.gouv.fr/cdn-cgi/challenge-platform/scripts/jsd/main.js
StorageType.persistent is deprecated. Please use standardized navigator.storage instead.	www.education.gouv.fr/cdn-cgi/challenge-platform/scripts/jsd/main.js
Fledge	www.education.gouv.fr/cdn-cgi/challenge-platform/scripts/jsd/main.js

●Uses HTTPS

●Avoids third-party cookies

●Allows users to paste into input fields

●Avoids requesting the geolocation permission on page load

●Avoids requesting the notification permission on page load

●Displays images with correct aspect ratio

●Serves images with appropriate resolution

●Page has the HTML doctype

●Properly defines charset

●No browser errors logged to the console

●No issues in the `Issues` panel in Chrome Devtools

●Ensure CSP is effective against XSS attacks

●Use a strong HSTS policy

●Ensure proper origin isolation with COOP

●Mitigate 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

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

Meta descriptions may be included in search results to concisely summarize page content. Learn more about the meta description.

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

●Page has successful HTTP status code

●Links have descriptive text

●Links are crawlable

●robots.txt is valid

●Image elements have `[alt]` attributes

●Document has a valid `hreflang`

●Document has a valid `rel=canonical`