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
/signals/config/537872945975515?v=2.9.313&r=stable&domain...	1200.0 s	125.2 KiB
connect.facebook.net/en_US/fbevents.js	1200.0 s	97.1 KiB
consent.cookiebot.com/uc.js	177.0 s	35.7 KiB
kit.fontawesome.com/8c5fb68f3d.js	60.0 s	5.7 KiB
/consentconfig/019efa7a-a19b-434f-acfa-4bdd81c203f0/stib-...	65571.0 s	693 B
/tr/?id=537872945975515&ev=PageView&dl=https%3A%2F%2Fwww....	0.0 ms	16 B
kit.fontawesome.com/8c5fb68f3d.js	60.0 s	0 B

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

Why this matters

Performance issues directly impact user engagement and conversion rates.

headings: [map[key:node label:Element subItemsHeading:map[key:extra] valueType:node] map[granularity:0.001 key:score label:Layout shift score subItemsHeading:map[key:cause valueType:text] valueType:numeric]]

items: [map[node:map[type:text value:Total] score:3.5e-05] map[score:3.5e-05 subItems:map[items:[map[cause:Unsized image element extra:map[boundingRect:map[bottom:374 height:32 left:28 right:50 top:342 width:22] lhId:page-10-IMG nodeLabel:div.row > div.col > h2.page-subtitle > img path:1,HTML,1,BODY,4,MAIN,0,DIV,1,DIV,1,DIV,0,DIV,0,DIV,0,DIV,0,H2,0,IMG selector:div.row > div.col > h2.page-subtitle > img snippet:<img src="/modules/stibmivb-core/images/gif/realtime.gif" alt=""> type:node]]] type:subitems]]]

items: [map[node:map[type:text value:Total] score:0.113422] map[node:map[boundingRect:map[bottom:1326 height:474 left:12 right:400 top:852 width:388] lhId:page-2-DIV nodeLabel:Travelling in Brussels? Plan your journey! From To Today Calculate the route path:1,HTML,1,BODY,4,MAIN,0,DIV,1,DIV,1,DIV,0,DIV,1,DIV,1,DIV selector:div.container > div.travel > div.row > div.col-12 snippet:<div class="col-12 col-lg-5"> type:node] score:0.103712 subItems:map[items:[map[cause:Unsized image element extra:map[boundingRect:map[bottom:4585 height:40 left:28 right:68 top:4545 width:40] lhId:page-11-IMG nodeLabel:AnySurfer accessibility status page path:1,HTML,1,BODY,6,FOOTER,2,DIV,0,DIV,0,DIV,1,DIV,0,A,0,IMG selector:div.row > div.col-auto > a > img snippet:<img src="/files/live/sites/STIBMIVB/files/template/label_anysurfer_40x40.png" alt="AnySurfer accessibility status page"> type:node]]] type:subitems]] map[node:map[boundingRect:map[bottom:1326 height:474 left:12 right:400 top:852 width:388] lhId:page-2-DIV nodeLabel:Travelling in Brussels? Plan your journey! From To Today Calculate the route path:1,HTML,1,BODY,4,MAIN,0,DIV,1,DIV,1,DIV,0,DIV,1,DIV,1,DIV selector:div.container > div.travel > div.row > div.col-12 snippet:<div class="col-12 col-lg-5"> type:node] score:0.007595 subItems:map[items:[map[cause:Web font extra:map[type:url value:https://ka-p.fontawesome.com/releases/v6.7.2/webfonts/pro-fa-brands-400-0.woff2]] map[cause:Web font extra:map[type:url value:https://ka-p.fontawesome.com/releases/v6.7.2/webfonts/pro-fa-regular-400-2.woff2]] map[cause:Web font extra:map[type:url value:https://ka-p.fontawesome.com/releases/v6.7.2/webfonts/pro-fa-regular-400-0.woff2]] map[cause:Web font extra:map[type:url value:https://ka-p.fontawesome.com/releases/v6.7.2/webfonts/pro-fa-solid-900-0.woff2]] map[cause:Web font extra:map[type:url value:https://ka-p.fontawesome.com/releases/v6.7.2/webfonts/pro-fa-solid-900-1.woff2]] map[cause:Web font extra:map[type:url value:https://ka-p.fontawesome.com/releases/v6.7.2/webfonts/pro-fa-brands-400-1.woff2]]] type:subitems]] map[node:map[boundingRect:map[bottom:945 height:56 left:113 right:311 top:889 width:198] lhId:page-4-H3 nodeLabel:Travelling in Brussels? Plan your journey! path:1,HTML,1,BODY,4,MAIN,0,DIV,1,DIV,1,DIV,0,DIV,1,DIV,1,DIV,0,DIV,0,DIV,1,H3 selector:div.col-12 > div#TripPlannerHome > div.title > h3.page-third-title snippet:<h3 class="page-third-title"> type:node] score:0.00169 subItems:map[items:[map[cause:Unsized image element extra:map[boundingRect:map[bottom:942 height:50 left:53 right:89 top:892 width:36] lhId:page-12-IMG nodeLabel:div.col-12 > div#TripPlannerHome > div.title > img path:1,HTML,1,BODY,4,MAIN,0,DIV,1,DIV,1,DIV,0,DIV,1,DIV,1,DIV,0,DIV,0,DIV,0,IMG selector:div.col-12 > div#TripPlannerHome > div.title > img snippet:<img src="/files/live/sites/STIBMIVB/files/template/svg/home_itinerary_pin.svg" alt=""> type:node]]] type:subitems]] map[node:map[boundingRect:map[bottom:47 height:27 left:185 right:388 top:20 width:203] lhId:page-1-DIV nodeLabel:Cart path:1,HTML,1,BODY,3,HEADER,0,NAV,1,DIV,0,DIV,2,DIV selector:nav.nav-primary > div.container-fluid > div.row > div.col-auto snippet:<div class="col-auto nav-primary-action d-flex justify-content-end flex-grow-1"> type:node] score:0.000356] map[node:map[boundingRect:map[bottom:467 height:60 left:198 right:257 top:407 width:59] lhId:page-5-LI nodeLabel:Bus path:1,HTML,1,BODY,4,MAIN,0,DIV,1,DIV,1,DIV,0,DIV,1,DIV,0,DIV,0,DIV,0,DIV,0,UL,3,LI selector:div#RTLinesAndTimetable > div.realtime-lines-nav > ul.nav-pills > li.nav-item snippet:<li class="nav-item"> type:node] score:6.3e-05 subItems:map[items:[map[cause:Unsized image element extra:map[boundingRect:map[bottom:4585 height:40 left:28 right:68 top:4545 width:40] lhId:page-11-IMG nodeLabel:AnySurfer accessibility status page path:1,HTML,1,BODY,6,FOOTER,2,DIV,0,DIV,0,DIV,1,DIV,0,A,0,IMG selector:div.row > div.col-auto > a > img snippet:<img src="/files/live/sites/STIBMIVB/files/template/label_anysurfer_40x40.png" alt="AnySurfer accessibility status page"> type:node]] map[cause:Web font extra:map[type:url value:https://ka-p.fontawesome.com/releases/v6.7.2/webfonts/pro-fa-solid-900-14.woff2]] map[cause:Web font extra:map[type:url value:https://ka-p.fontawesome.com/releases/v6.7.2/webfonts/pro-fa-solid-900-11.woff2]]] type:subitems]]]

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.

URL	Est Savings
/modules/stibmivb-template/css/fonts/brusseline-bold-webf...	80 ms
ka-p.fontawesome.com/releases/v6.7.2/webfonts/pro-fa-brands-400-0.woff2	35 ms
ka-p.fontawesome.com/releases/v6.7.2/webfonts/pro-fa-regular-400-2.woff2	25 ms
ka-p.fontawesome.com/releases/v6.7.2/webfonts/pro-fa-brands-400-1.woff2	25 ms
ka-p.fontawesome.com/releases/v6.7.2/webfonts/pro-fa-regular-400-0.woff2	20 ms
ka-p.fontawesome.com/releases/v6.7.2/webfonts/pro-fa-solid-900-0.woff2	20 ms
ka-p.fontawesome.com/releases/v6.7.2/webfonts/pro-fa-solid-900-1.woff2	20 ms
ka-p.fontawesome.com/releases/v6.7.2/webfonts/pro-fa-regular-400-12.woff2	20 ms
ka-p.fontawesome.com/releases/v6.7.2/webfonts/pro-fa-solid-900-11.woff2	20 ms
ka-p.fontawesome.com/releases/v6.7.2/webfonts/pro-fa-regular-400-14.woff2	15 ms
ka-p.fontawesome.com/releases/v6.7.2/webfonts/pro-fa-solid-900-4.woff2	15 ms
ka-p.fontawesome.com/releases/v6.7.2/webfonts/pro-fa-solid-900-14.woff2	15 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:Top function call valueType:source-location] map[granularity:1 key:reflowTime label:Total reflow time valueType:ms]]

items: [map[reflowTime:5.736 source:map[column:1.148343e+06 line:1 type:source-location url:https://www.stib-mivb.be/modules/stibmivb-template/javascript/main-rrfkY9Wl.js urlProvider:network]]]

headings: [map[key:source label:Source valueType:source-location] map[granularity:1 key:reflowTime label:Total reflow time valueType:ms]]

items: [map[reflowTime:74.434 source:map[type:text value:[unattributed]]] map[reflowTime:24.813 source:map[column:23992 line:61 type:source-location url:https://www.stib-mivb.be/modules/stibmivb-template/javascript/main-rrfkY9Wl.js urlProvider:network]] map[reflowTime:1.935 source:map[column:90664 line:4 type:source-location url:https://www.stib-mivb.be/modules/stibmivb-template/javascript/main-rrfkY9Wl.js urlProvider:network]] map[reflowTime:2.764 source:map[column:1.168336e+06 line:0 type:source-location url:https://www.stib-mivb.be/modules/stibmivb-template/javascript/main-rrfkY9Wl.js urlProvider:network]] map[reflowTime:5.381 source:map[column:1.131809e+06 line:0 type:source-location url:https://www.stib-mivb.be/modules/stibmivb-template/javascript/main-rrfkY9Wl.js urlProvider:network]]]

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-DIV

nodeLabel: Let's move Brussels

path: 1,HTML,1,BODY,4,MAIN,0,DIV,0,DIV

selector: body > main#content > div.home > div.home-banner

snippet: <div class="home-banner" style="--img-desktop: url('/files/live/sites/STIBMIVB/files/__LGBTQ%20-%201440X320…;">

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
www.stib-mivb.be/modules/stibmivb-template/css/main_NW_2026_07.css	95.1 KiB	1.3 s
www.stib-mivb.be/modules/stibmivb-template/css/cookiecss.css	3.9 KiB	539 ms
www.stib-mivb.be/modules/stibmivb-template/javascript/tracking_NW_2025_16.js	2.7 KiB
consent.cookiebot.com/uc.js	35.7 KiB	1.2 s
fonts.googleapis.com/css2?family=Inter:wght@400;500;600;700&display=swap	1.2 KiB	778 ms

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
div.swiper-slide > div.related-article > div.picture > img.img-fluid `div.swiper-slide > div.related-article > div.picture > img.img-fluid`	/files/live/sites/STIBMIVB/files/Corporate/banners/122155...	251.1 KiB	225.3 KiB
div.swiper-slide > div.related-article > div.picture > img.img-fluid `div.swiper-slide > div.related-article > div.picture > img.img-fluid`	/files/live/sites/STIBMIVB/files/Corporate/Banner-site-st...	148.8 KiB	122.9 KiB
div.card-highlighted-content > div.content-wrapper > div.picture > img.img-fluid `div.card-highlighted-content > div.content-wrapper > div.picture > img.img-fluid`	www.stib-mivb.be/files/live/sites/STIBMIVB/files/Buy/EMV.png	67.3 KiB	64.1 KiB

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.

URL	Protocol
www.stib-mivb.be/home	http/1.1
www.stib-mivb.be/modules/stibmivb-template/javascript/tracking_NW_2025_16.js	http/1.1
www.stib-mivb.be/modules/stibmivb-template/css/main_NW_2026_07.css	http/1.1
www.stib-mivb.be/modules/stibmivb-template/css/cookiecss.css	http/1.1
/files/live/sites/STIBMIVB/files/Legal/Homepage/sitb-mivb...	http/1.1
www.stib-mivb.be/modules/stibmivb-template/images/svg/icon_search.svg	http/1.1
www.stib-mivb.be/modules/stibmivb-login/images/svg/icon_account_offline.svg	http/1.1
www.stib-mivb.be/modules/stibmivb-eshop/images/svg/icon_basket.svg	http/1.1
www.stib-mivb.be/modules/stibmivb-template/javascript/vendors.js	http/1.1
www.stib-mivb.be/modules/stibmivb-core/images/gif/realtime.gif	http/1.1
www.stib-mivb.be/files/live/sites/STIBMIVB/files/Travel/works.svg	http/1.1
www.stib-mivb.be/files/live/sites/STIBMIVB/files/Personnages/Tenez-vous.svg	http/1.1
/files/live/sites/STIBMIVB/files/Personnages/Personne ave...	http/1.1
www.stib-mivb.be/files/live/sites/STIBMIVB/files/Buy/EMV.png	http/1.1
www.stib-mivb.be/files/live/sites/STIBMIVB/files/Travel/Floya_App-Icon_Apple.svg	http/1.1
www.stib-mivb.be/files/live/sites/STIBMIVB/files/Personnages/Group%20809.svg	http/1.1
/files/live/sites/STIBMIVB/files/template/label_anysurfer...	http/1.1
www.stib-mivb.be/modules/stibmivb-template/javascript/main-rrfkY9Wl.js	http/1.1
www.stib-mivb.be/files/live/sites/STIBMIVB/files/template/store.svg	http/1.1
www.stib-mivb.be/modules/stibmivb-template/images/favicon/site.webmanifest	http/1.1
www.stib-mivb.be/files/live/sites/STIBMIVB/files/__LGBTQ%20-%20960X320.svg	http/1.1
www.stib-mivb.be/modules/stibmivb-template/images/svg/home_wave_top.svg	http/1.1
/modules/stibmivb-template/css/fonts/brusseline-bold-webf...	http/1.1
www.stib-mivb.be/modules/stibmivb-template/images/favicon/favicon-32x32.png	http/1.1
/files/live/sites/STIBMIVB/files/Travel/Travaux/ATTENTION...	http/1.1
/files/live/sites/STIBMIVB/files/Corporate/banners/122155...	http/1.1
/files/live/sites/STIBMIVB/files/Corporate/Banner-site-st...	http/1.1
/files/live/sites/STIBMIVB/files/template/svg/home_itiner...	http/1.1

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.

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: 2.1 s

URL	Time Spent
stib-mivb.brussels/	1.0 s
www.stib-mivb.be/	1.0 s
www.stib-mivb.be/home	0.0 ms

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

Why this matters

Performance issues directly impact user engagement and conversion rates.

Element	Layout shift score
Travelling in Brussels? Plan your journey! From To Today Calculate the route `div.container > div.travel > div.row > div.col-12`	0.104
Travelling in Brussels? Plan your journey! From To Today Calculate the route `div.container > div.travel > div.row > div.col-12`	0.008
Travelling in Brussels? Plan your journey! `div.col-12 > div#TripPlannerHome > div.title > h3.page-third-title`	0.002
Cart `nav.nav-primary > div.container-fluid > div.row > div.col-auto`	0.000
Bus `div#RTLinesAndTimetable > div.realtime-lines-nav > ul.nav-pills > li.nav-item`	0.000
	0.000
div.itinerary-search-form > div.itinerary-search-form-places > button.btn > i.fa `div.itinerary-search-form > div.itinerary-search-form-places > button.btn > i.fa`	0.000

Diagnostics

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

Why this matters

Performance issues directly impact user engagement and conversion rates.

Estimated savings: 1.1 s 135.0 KiB

URL	Transfer Size	Est Savings
www.stib-mivb.be/modules/stibmivb-template/css/main_NW_2026_07.css	94.3 KiB	87.1 KiB
@charset "utf-8";.fa{font-family:var(--fa-style-family,"Font Awesome 6 Pro"); … } …	48.3 KiB	47.8 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.

URL	Total CPU Time	Script Evaluation	Script Parse
www.stib-mivb.be/modules/stibmivb-template/javascript/main-rrfkY9Wl.js	1.9 s	1.2 s	440 ms
www.stib-mivb.be/home	1.2 s	9.9 ms	2.6 ms
Unattributable	1.1 s	75 ms	0.0 ms
/gtm.js?id=GTM-NR8C6F27&gtm_auth=g3wZAhZGvfleAd4TmVXo8g&&...	618 ms	516 ms	91 ms
www.stib-mivb.be/modules/stibmivb-template/javascript/vendors.js	546 ms	23 ms	501 ms
/gtag/js?id=AW-875372945&cx=c&gtm=4e6562&sign=e4fb3875ec5...	328 ms	275 ms	49 ms
/signals/config/537872945975515?v=2.9.313&r=stable&domain...	300 ms	248 ms	50 ms
consent.cookiebot.com/uc.js	287 ms	250 ms	15 ms
/gtag/js?id=DC-4708247&cx=c&gtm=4e6562&sign=e4fb3875ec5d0...	220 ms	162 ms	54 ms
/gtag/js?id=G-XXXXXXXXXX&cx=c&gtm=4e6562&sign=e4fb3875ec5...	216 ms	161 ms	54 ms
connect.facebook.net/en_US/fbevents.js	199 ms	149 ms	48 ms
/019efa7a-a19b-434f-acfa-4bdd81c203f0/cc.js?renew=false&r...	85 ms	82 ms	0.4 ms
www.stib-mivb.be/modules/stibmivb-template/css/main_NW_2026_07.css	53 ms	0.0 ms	0.0 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.

Category	Time Spent
Script Evaluation	3.2 s
Other	1.4 s
Script Parsing & Compilation	1.3 s
Style & Layout	810 ms
Rendering	223 ms
Garbage Collection	138 ms
Parse HTML & CSS	74 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 reason	Failure type
Pages with cache-control:no-store header cannot enter back/forward cache.	Actionable
Pages whose main resource has cache-control:no-store cannot enter back/forward cache.	Not actionable
Back/forward cache is disabled because some JavaScript network request received resource with Cache-Control: no-store header.	Not actionable

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 320.2 KiB

URL	Transfer Size	Est Savings
www.stib-mivb.be/modules/stibmivb-template/javascript/vendors.js	971.2 KiB	320.2 KiB

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

Why this matters

Performance issues directly impact user engagement and conversion rates.

Estimated savings: 0.0 ms 1.7 MiB

URL	Transfer Size	Est Savings
www.stib-mivb.be/modules/stibmivb-template/javascript/vendors.js	971.2 KiB	681.0 KiB
www.stib-mivb.be/modules/stibmivb-template/javascript/main-rrfkY9Wl.js	1.1 MiB	538.3 KiB
/gtag/js?id=G-XXXXXXXXXX&cx=c&gtm=4e6562&sign=e4fb3875ec5...	380.7 KiB	195.8 KiB
/gtm.js?id=GTM-NR8C6F27&gtm_auth=g3wZAhZGvfleAd4TmVXo8g&&...	533.3 KiB	190.5 KiB
/gtag/js?id=DC-4708247&cx=c&gtm=4e6562&sign=e4fb3875ec5d0...	130.0 KiB	60.4 KiB
/gtag/js?id=AW-875372945&cx=c&gtm=4e6562&sign=e4fb3875ec5...	145.3 KiB	52.6 KiB
/signals/config/537872945975515?v=2.9.313&r=stable&domain...	125.0 KiB	35.2 KiB
connect.facebook.net/en_US/fbevents.js	97.0 KiB	35.0 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.

URL	Transfer Size
www.stib-mivb.be/modules/stibmivb-template/javascript/main-rrfkY9Wl.js	1.1 MiB
www.stib-mivb.be/modules/stibmivb-template/javascript/vendors.js	972.1 KiB
/gtm.js?id=GTM-NR8C6F27&gtm_auth=g3wZAhZGvfleAd4TmVXo8g&&...	533.6 KiB
/gtag/js?id=G-XXXXXXXXXX&cx=c&gtm=4e6562&sign=e4fb3875ec5...	381.0 KiB
/files/live/sites/STIBMIVB/files/Corporate/banners/122155...	252.0 KiB
/files/live/sites/STIBMIVB/files/Corporate/Banner-site-st...	149.6 KiB
/gtag/js?id=AW-875372945&cx=c&gtm=4e6562&sign=e4fb3875ec5...	145.3 KiB
/gtag/js?id=DC-4708247&cx=c&gtm=4e6562&sign=e4fb3875ec5d0...	130.2 KiB
www.stib-mivb.be/files/live/sites/STIBMIVB/files/template/store.svg	128.8 KiB
/signals/config/537872945975515?v=2.9.313&r=stable&domain...	125.2 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.card-highlighted-content > div.content-wrapper > div.picture > img.img-fluid `div.card-highlighted-content > div.content-wrapper > div.picture > img.img-fluid`	www.stib-mivb.be/files/live/sites/STIBMIVB/files/Buy/EMV.png
Return to the homepage stib-mivb.be `div.row > div.col-auto > a#home-logo > img`	/files/live/sites/STIBMIVB/files/Legal/Homepage/sitb-mivb...
ul.row > li.col-12 > div.card > img.picture `ul.row > li.col-12 > div.card > img.picture`	www.stib-mivb.be/files/live/sites/STIBMIVB/files/Personnages/Tenez-vous.svg
ul.row > li.col-12 > div.card > img.picture `ul.row > li.col-12 > div.card > img.picture`	/files/live/sites/STIBMIVB/files/Personnages/Personne ave...
div.card-highlighted-content > div.content-wrapper > div.picture > img.img-fluid `div.card-highlighted-content > div.content-wrapper > div.picture > img.img-fluid`	www.stib-mivb.be/files/live/sites/STIBMIVB/files/Travel/works.svg
div.col-12 > div#TripPlannerHome > div.title > img `div.col-12 > div#TripPlannerHome > div.title > img`	/files/live/sites/STIBMIVB/files/template/svg/home_itiner...
AnySurfer accessibility status page `div.row > div.col-auto > a > img`	/files/live/sites/STIBMIVB/files/template/label_anysurfer...
div.row > div.col > h2.page-subtitle > img `div.row > div.col > h2.page-subtitle > img`	www.stib-mivb.be/modules/stibmivb-core/images/gif/realtime.gif

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

●Optimize DOM size

●LCP breakdown

●Optimize viewport for mobile

●Minify CSS

●Avoid long main-thread tasks 20 long tasks found

●Avoid non-composited animations 4 animated elements found

●Network Requests

●Network Round Trip Times 80 ms

●Server Backend Latencies 170 ms

●Tasks

●Diagnostics

●Metrics

●Screenshot Thumbnails

●Final Screenshot

●Script Treemap Data

●Resources Summary

●Initial server response time was short Root document took 80 ms

○INP breakdown

○User Timing marks and measures

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.

ARIA

Some ARIA parent roles must contain specific child roles to perform their intended accessibility functions. Learn more about roles and required children elements.

Why this matters

Performance issues directly impact user engagement and conversion rates.

Failing Elements
All Metro Tram Bus `div.col-12 > div#RTLinesAndTimetable > div.realtime-lines-nav > ul.nav-pills`

Some ARIA child roles must be contained by specific parent roles to properly perform their intended accessibility functions. Learn more about ARIA roles and required parent element.

Why this matters

Performance issues directly impact user engagement and conversion rates.

Failing Elements
All `div.realtime-lines-nav > ul.nav-pills > li.nav-item > button#react-aria5690077141-1-tab-a`
Metro `div.realtime-lines-nav > ul.nav-pills > li.nav-item > button#react-aria5690077141-1-tab-METRO`
Tram `div.realtime-lines-nav > ul.nav-pills > li.nav-item > button#react-aria5690077141-1-tab-TRAM`
Bus `div.realtime-lines-nav > ul.nav-pills > li.nav-item > button#react-aria5690077141-1-tab-BUS`

These are opportunities to improve the usage of ARIA in your application which may enhance the experience for users of assistive technology, like a screen reader.

Names and labels

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

Why this matters

Performance issues directly impact user engagement and conversion rates.

Failing Elements
Today `div.form-line > div.input-group > div.dropdown > button#buttonFilterDropdownStartTimeDay`

Labels ensure that form controls are announced properly by assistive technologies, like screen readers. Learn more about form element labels.

Why this matters

Performance issues directly impact user engagement and conversion rates.

Failing Elements
div.col-12 > div.form-line > div.input-group > input#StartTime `div.col-12 > div.form-line > div.input-group > input#StartTime`

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 > a `body > 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. Learn how to provide sufficient color contrast.

Why this matters

Performance issues directly impact user engagement and conversion rates.

Failing Elements
M5 `div#swiper-wrapper-a5c1b6fb7a5105da5 > ul.swiper-slide > li > a.line-number`
12 `div#swiper-wrapper-a5c1b6fb7a5105da5 > ul.swiper-slide > li > a.line-number`
17 `div#swiper-wrapper-a5c1b6fb7a5105da5 > ul.swiper-slide > li > a.line-number`
19 `div#swiper-wrapper-a5c1b6fb7a5105da5 > ul.swiper-slide > li > a.line-number`
28 `div#swiper-wrapper-a5c1b6fb7a5105da5 > ul.swiper-slide > li > a.line-number`
29 `div#swiper-wrapper-a5c1b6fb7a5105da5 > ul.swiper-slide > li > a.line-number`
38 `div#swiper-wrapper-a5c1b6fb7a5105da5 > ul.swiper-slide > li > a.line-number`
39 `div#swiper-wrapper-a5c1b6fb7a5105da5 > ul.swiper-slide > li > a.line-number`
42 `div#swiper-wrapper-a5c1b6fb7a5105da5 > ul.swiper-slide > li > a.line-number`

These are opportunities to improve the legibility of your content.

Tables and lists

Screen readers require list items (`<li>`) to be contained within a parent `<ul>`, `<ol>` or `<menu>` to be announced properly. Learn more about proper list structure.

Why this matters

Performance issues directly impact user engagement and conversion rates.

Failing Elements
All `div#RTLinesAndTimetable > div.realtime-lines-nav > ul.nav-pills > li.nav-item`
Metro `div#RTLinesAndTimetable > div.realtime-lines-nav > ul.nav-pills > li.nav-item`
Tram `div#RTLinesAndTimetable > div.realtime-lines-nav > ul.nav-pills > li.nav-item`
Bus `div#RTLinesAndTimetable > div.realtime-lines-nav > ul.nav-pills > li.nav-item`

These are opportunities to improve the experience of reading tabular or list data using assistive technology, like a screen reader.

○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

●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

●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>`).

●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

●`<html>` element has an `[xml:lang]` attribute with the same base language as the `[lang]` attribute.

●Document has a main landmark.

●Deprecated ARIA roles were not used

○`[accesskey]` values are unique

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

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

○ARIA input fields have accessible names

○ARIA `meter` elements have accessible names

○ARIA `progressbar` elements have accessible names

○Elements with 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

○Input buttons have discernible text.

○`<input type="image">` elements have `[alt]` text

○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.

○`<video>` elements contain a `<track>` element with `[kind="captions"]`

○Tables have different content in the summary attribute and `<caption>`.

○All heading elements contain content.

○Uses ARIA roles only on compatible elements

○Image elements do not have `[alt]` attributes that are redundant text.

○Identical links have the same purpose.

○Elements with visible text labels have matching accessible names.

○Tables use `<caption>` instead of cells with the `[colspan]` attribute to indicate a caption.

○`<td>` elements in a large `<table>` have one or more table headers.

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.

	URL	Displayed size	Actual size	Expected size
div.row > div.col > h2.page-subtitle > img `div.row > div.col > h2.page-subtitle > img`	www.stib-mivb.be/modules/stibmivb-core/images/gif/realtime.gif	22 x 32	22 x 32	33 x 48

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
AttributionReporting	/gtag/js?id=AW-875372945&cx=c&gtm=4e6562&sign=e4fb3875ec5... line 583, col 229

Source maps translate minified code to the original source code. This helps developers debug in production. In addition, Lighthouse is able to provide further insights. Consider deploying source maps to take advantage of these benefits. Learn more about source maps.

Why this matters

Performance issues directly impact user engagement and conversion rates.

URL	Map URL
www.stib-mivb.be/modules/stibmivb-template/javascript/vendors.js
www.stib-mivb.be/modules/stibmivb-template/javascript/main-rrfkY9Wl.js
/gtm.js?id=GTM-NR8C6F27&gtm_auth=g3wZAhZGvfleAd4TmVXo8g&&...
cdn.jsdelivr.net/npm/bootstrap@5.0.2/dist/js/bootstrap.bundle.min.js	cdn.jsdelivr.net/npm/bootstrap@5.0.2/dist/js/bootstrap.bundle.min.js.map

●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 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

○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.

Crawling and Indexing

If your robots.txt file is malformed, crawlers may not be able to understand how you want your website to be crawled or indexed. Learn more about robots.txt.

Why this matters

Performance issues directly impact user engagement and conversion rates.

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

●Links have descriptive text

●Links are crawlable

●Image elements have `[alt]` attributes

●Document has a valid `hreflang`

●Document has a valid `rel=canonical`