Lighthouse Desktop

· 0 checks — Desktop 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.

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:0.880668] map[node:map[boundingRect:map[bottom:13252 height:12955 left:0 right:1350 top:297 width:1350] lhId:page-10-MAIN nodeLabel:NRC - Nieuws, achtergronden en onderzoeksjournalistiek ENERGIEMAATREGELEN Kabin… path:1,HTML,1,BODY,8,MAIN selector:body.indexpage > main#main-content snippet:<main id="main-content" tabindex="-1"> type:node] score:0.815451 subItems:map[items:[map[cause:Unsized image element extra:map[boundingRect:map[bottom:2172 height:72 left:990 right:1110 top:2100 width:120] lhId:page-22-IMG nodeLabel:a.photo-articles-gtm-click > figure.image > picture.photo-articles-gtm-click > img.photo-articles-gtm-click path:1,HTML,1,BODY,8,MAIN,2,DIV,0,DIV,0,DIV,0,DIV,0,DIV,0,DIV,1,DIV,3,SECTION,0,DIV,0,DIV,0,SECTION,1,UL,0,LI,0,A,0,FIGURE,0,PICTURE,0,IMG selector:a.photo-articles-gtm-click > figure.image > picture.photo-articles-gtm-click > img.photo-articles-gtm-click snippet:<img alt="" srcset=" https://images.nrc.nl/DZ0lPbQQj_6_s9UV7spFOjdo63o=/0x82:5892x3617/160x96…" src="https://images.nrc.nl/DZ0lPbQQj_6_s9UV7spFOjdo63o=/0x82:5892x3617/160x96/s…" decoding="async" width="160" height="96" class="photo-articles-gtm-click"> type:node]]] type:subitems]] map[node:map[boundingRect:map[bottom:13252 height:12955 left:0 right:1350 top:297 width:1350] lhId:page-10-MAIN nodeLabel:NRC - Nieuws, achtergronden en onderzoeksjournalistiek ENERGIEMAATREGELEN Kabin… path:1,HTML,1,BODY,8,MAIN selector:body.indexpage > main#main-content snippet:<main id="main-content" tabindex="-1"> type:node] score:0.060451 subItems:map[items:[map[cause:Unsized image element extra:map[boundingRect:map[bottom:2172 height:72 left:990 right:1110 top:2100 width:120] lhId:page-22-IMG nodeLabel:a.photo-articles-gtm-click > figure.image > picture.photo-articles-gtm-click > img.photo-articles-gtm-click path:1,HTML,1,BODY,8,MAIN,2,DIV,0,DIV,0,DIV,0,DIV,0,DIV,0,DIV,1,DIV,3,SECTION,0,DIV,0,DIV,0,SECTION,1,UL,0,LI,0,A,0,FIGURE,0,PICTURE,0,IMG selector:a.photo-articles-gtm-click > figure.image > picture.photo-articles-gtm-click > img.photo-articles-gtm-click snippet:<img alt="" srcset=" https://images.nrc.nl/DZ0lPbQQj_6_s9UV7spFOjdo63o=/0x82:5892x3617/160x96…" src="https://images.nrc.nl/DZ0lPbQQj_6_s9UV7spFOjdo63o=/0x82:5892x3617/160x96/s…" decoding="async" width="160" height="96" class="photo-articles-gtm-click"> type:node]]] type:subitems]] map[node:map[boundingRect:map[bottom:1973 height:12 left:990 right:1326 top:1961 width:336] lhId:page-9-DIV nodeLabel:div.block__news__inner > div.nmt-layout > div.nmt-layout__sidebar > div.native-ad-item-holder path:1,HTML,1,BODY,8,MAIN,2,DIV,0,DIV,0,DIV,0,DIV,0,DIV,0,DIV,1,DIV,2,DIV selector:div.block__news__inner > div.nmt-layout > div.nmt-layout__sidebar > div.native-ad-item-holder snippet:<div class="native-ad-item-holder native-ad-item-holder--below-more-news"> type:node] score:0.002365] map[node:map[boundingRect:map[bottom:232 height:61 left:862 right:1326 top:171 width:464] lhId:page-6-DIV nodeLabel:Abonneren Podcasts Digitale krant path:1,HTML,1,BODY,5,HEADER,4,DIV,0,DIV,2,DIV selector:header.header > div.header__main > div.header__inner-container > div.header__buttons snippet:<div class="header__buttons"> type:node] score:0.002115] map[node:map[boundingRect:map[bottom:295 height:62 left:0 right:978 top:233 width:978] lhId:page-1-UL nodeLabel:Binnenland Buitenland Economie Den Haag Cultuur Wetenschap Opinie Boeken Leven … path:1,HTML,1,BODY,5,HEADER,5,DIV,0,DIV,0,DIV,0,DIV,0,UL selector:div.header__sections-and-selections__inner > div.header__sections-bar > div.header__sections-bar__inner > ul snippet:<ul> type:node] score:0.000286 subItems:map[items:[map[cause:Web font extra:map[type:url value:https://assets.nrc.nl/static/front/fonts/GuardianEgyp-Regular-Web.a71963a16.woff2]] map[cause:Web font extra:map[type:url value:https://assets.nrc.nl/static/front/fonts/LFT_Etica_Reg.4bfcdd546.woff2]] map[cause:Web font extra:map[type:url value:https://assets.nrc.nl/static/front/fonts/GuardianTextEgyp-Regular-Web.0561af52a.woff2]] map[cause:Web font extra:map[type:url value:https://assets.nrc.nl/static/front/fonts/LFT_Etica_Book.8f783e38c.woff2]]] type:subitems]]]

items: [map[node:map[type:text value:Total] score:0.12226] map[node:map[boundingRect:map[bottom:950 height:0 left:990 right:1326 top:950 width:336] lhId:page-18-DIV nodeLabel:Laatste nieuws 22:08 ASIEL Opnieuw onrust in Loosdrecht, rechter oordeelt dat a… path:1,HTML,1,BODY,8,MAIN,2,DIV,0,DIV,0,DIV,0,DIV,0,DIV,0,DIV,1,DIV,1,DIV,0,DIV selector:div.nmt-layout > div.nmt-layout__sidebar > div > div.timed-articles snippet:<div class="timed-articles" data-timed-articles="" data-sticky="false"> type:node] score:0.070018 subItems:map[items:[map[cause:Unsized image element extra:map[boundingRect:map[bottom:2172 height:72 left:990 right:1110 top:2100 width:120] lhId:page-22-IMG nodeLabel:a.photo-articles-gtm-click > figure.image > picture.photo-articles-gtm-click > img.photo-articles-gtm-click path:1,HTML,1,BODY,8,MAIN,2,DIV,0,DIV,0,DIV,0,DIV,0,DIV,0,DIV,1,DIV,3,SECTION,0,DIV,0,DIV,0,SECTION,1,UL,0,LI,0,A,0,FIGURE,0,PICTURE,0,IMG selector:a.photo-articles-gtm-click > figure.image > picture.photo-articles-gtm-click > img.photo-articles-gtm-click snippet:<img alt="" srcset=" https://images.nrc.nl/DZ0lPbQQj_6_s9UV7spFOjdo63o=/0x82:5892x3617/160x96…" src="https://images.nrc.nl/DZ0lPbQQj_6_s9UV7spFOjdo63o=/0x82:5892x3617/160x96/s…" decoding="async" width="160" height="96" class="photo-articles-gtm-click"> type:node]]] type:subitems]] map[node:map[boundingRect:map[bottom:13252 height:12955 left:0 right:1350 top:297 width:1350] lhId:page-10-MAIN nodeLabel:NRC - Nieuws, achtergronden en onderzoeksjournalistiek ENERGIEMAATREGELEN Kabin… path:1,HTML,1,BODY,8,MAIN selector:body.indexpage > main#main-content snippet:<main id="main-content" tabindex="-1"> type:node] score:0.049169 subItems:map[items:[map[cause:Unsized image element extra:map[boundingRect:map[bottom:2172 height:72 left:990 right:1110 top:2100 width:120] lhId:page-22-IMG nodeLabel:a.photo-articles-gtm-click > figure.image > picture.photo-articles-gtm-click > img.photo-articles-gtm-click path:1,HTML,1,BODY,8,MAIN,2,DIV,0,DIV,0,DIV,0,DIV,0,DIV,0,DIV,1,DIV,3,SECTION,0,DIV,0,DIV,0,SECTION,1,UL,0,LI,0,A,0,FIGURE,0,PICTURE,0,IMG selector:a.photo-articles-gtm-click > figure.image > picture.photo-articles-gtm-click > img.photo-articles-gtm-click snippet:<img alt="" srcset=" https://images.nrc.nl/DZ0lPbQQj_6_s9UV7spFOjdo63o=/0x82:5892x3617/160x96…" src="https://images.nrc.nl/DZ0lPbQQj_6_s9UV7spFOjdo63o=/0x82:5892x3617/160x96/s…" decoding="async" width="160" height="96" class="photo-articles-gtm-click"> type:node]]] type:subitems]] map[node:map[boundingRect:map[bottom:13252 height:12955 left:0 right:1350 top:297 width:1350] lhId:page-10-MAIN nodeLabel:NRC - Nieuws, achtergronden en onderzoeksjournalistiek ENERGIEMAATREGELEN Kabin… path:1,HTML,1,BODY,8,MAIN selector:body.indexpage > main#main-content snippet:<main id="main-content" tabindex="-1"> type:node] score:0.003073 subItems:map[items:[map[cause:Unsized image element extra:map[boundingRect:map[bottom:2172 height:72 left:990 right:1110 top:2100 width:120] lhId:page-22-IMG nodeLabel:a.photo-articles-gtm-click > figure.image > picture.photo-articles-gtm-click > img.photo-articles-gtm-click path:1,HTML,1,BODY,8,MAIN,2,DIV,0,DIV,0,DIV,0,DIV,0,DIV,0,DIV,1,DIV,3,SECTION,0,DIV,0,DIV,0,SECTION,1,UL,0,LI,0,A,0,FIGURE,0,PICTURE,0,IMG selector:a.photo-articles-gtm-click > figure.image > picture.photo-articles-gtm-click > img.photo-articles-gtm-click snippet:<img alt="" srcset=" https://images.nrc.nl/DZ0lPbQQj_6_s9UV7spFOjdo63o=/0x82:5892x3617/160x96…" src="https://images.nrc.nl/DZ0lPbQQj_6_s9UV7spFOjdo63o=/0x82:5892x3617/160x96/s…" decoding="async" width="160" height="96" class="photo-articles-gtm-click"> type:node]]] 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.

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:7.336 source:map[column:25900 line:104 type:source-location url:https://assets.nrc.nl/static/front/js/vendor.0677b1b4d.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:18.593 source:map[type:text value:[unattributed]]] map[reflowTime:8.996 source:map[column:214017 line:0 type:source-location url:https://assets.nrc.nl/static/front/js/main.db164c9ed.js urlProvider:network]] map[reflowTime:1.671 source:map[column:583759 line:0 type:source-location url:https://assets.nrc.nl/static/front/js/main.db164c9ed.js urlProvider:network]] map[reflowTime:8.292 source:map[column:82845 line:103 type:source-location url:https://assets.nrc.nl/static/front/js/vendor.0677b1b4d.js urlProvider:network]] map[reflowTime:1.95 source:map[column:76610 line:103 type:source-location url:https://assets.nrc.nl/static/front/js/vendor.0677b1b4d.js urlProvider:network]] map[reflowTime:0.328 source:map[column:57 line:24 type:source-location url:https://static.chartbeat.com/js/chartbeat.js urlProvider:network]] map[reflowTime:0.255 source:map[column:123 line:23 type:source-location url:https://static.chartbeat.com/js/chartbeat.js urlProvider:network]] map[reflowTime:15.894 source:map[column:588440 line:0 type:source-location url:https://assets.nrc.nl/static/front/js/main.db164c9ed.js urlProvider:network]] map[reflowTime:0.272 source:map[column:198914 line:0 type:source-location url:https://assets.nrc.nl/static/front/js/main.db164c9ed.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-IMG

nodeLabel: div.nmt-item__image-wrapper > figure.responsive-figure > picture > img

path: 1,HTML,1,BODY,8,MAIN,2,DIV,0,DIV,0,DIV,0,DIV,0,DIV,0,DIV,0,DIV,0,SECTION,1,DIV,0,DIV,0,DIV,0,DIV,0,A,0,DIV,0,FIGURE,0,PICTURE,0,IMG

selector: div.nmt-item__image-wrapper > figure.responsive-figure > picture > img

snippet: <img alt="" srcset=" https://images.nrc.nl/8XyoJK90LW_L9qeALR92gektZqQ=/160x96/smart/filters:…" src="https://images.nrc.nl/-i4B3fO8tgxuulp_G33CUeLD4q0=/640x384/smart/filters:n…" decoding="async" sizes=" (min-width: 1408px) calc(.5 * 988px), (min-width: 980px) …" width="160" height="96" class="" pinger-seen="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

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.

URL	Transfer Size	Duration
assets.nrc.nl/static/front/css/split/index.d7cde8467.css	8.9 KiB
assets.nrc.nl/static/front/css/main.11aa071ef.css	13.2 KiB	556 ms
assets.nrc.nl/static/front/css/split/timed-articles.140afb3fc.css	764 B
assets.nrc.nl/static/front/css/split/layout-home.0f6721656.css	416 B
assets.nrc.nl/static/front/css/split/vorm-variables.fa674b062.css	1.6 KiB
assets.nrc.nl/static/front/css/split/header-and-footer.5e49114f3.css	5.4 KiB	68 ms

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
prod-nrcm.mhtr.be/public/tr/tracker.min.js	14400.0 s	159.3 KiB
cdn.sophi.io/assets/demeter/1/stable/3569875221.js?isConsented=true	900.0 s	40.9 KiB
cdn.optoutadvertising.com/script/sf/base.js	0.0 ms	24.1 KiB
/11ef8ac9-6270-4d5e-8b99-8d6a5bd60059/loader.js?target_ty...	7200.0 s	31.1 KiB
content3.nrc.nl/script/ootag.v2.min.js	0.0 ms	18.8 KiB
cdn.optoutadvertising.com/script/sf/ext.js	0.0 ms	15.6 KiB
static.chartbeat.com/js/chartbeat.js	7200.0 s	16.1 KiB
/pub/163/prod/display/483321/rehosted_oo/scripts/15/webod...	0.0 ms	10.4 KiB
cdn.optoutadvertising.com/script/sf/hostOptOut.min.js	0.0 ms	9.6 KiB
static.hotjar.com/c/hotjar-298877.js?sv=7	60.0 s	9.2 KiB
static.chartbeat.com/js/chartbeat_mab.js	7200.0 s	10.1 KiB
cdn.optoutadvertising.com/script/sf/base.min.js	0.0 ms	6.0 KiB
bgmin.cdn.billygrace.com/?t=1776902400000&v=0.1.0.1	0.0 ms	5.7 KiB
content3.nrc.nl/script/viewability.js	0.0 ms	4.3 KiB
content3.nrc.nl/script/mraidSideBridge.js	0.0 ms	2.9 KiB
/b2?c1=2&c2=11546962&ns_site=total&cs_fpid=1776892034618_...	0.0 ms	303 B
/pixel?https%3A%2F%2Fadserving.optoutadvertising.com%2Fev...	0.0 ms	184 B
/pixel?https%3A%2F%2Fadserving.optoutadvertising.com%2Fev...	0.0 ms	183 B
/pixel?https://adserving.optoutadvertising.com/viewable?b...	0.0 ms	183 B
sb.scorecardresearch.com/internal-c2/default/cs.js	86400.0 s	359 B
cdn.optoutadvertising.com/script/sf/base.js	0.0 ms	0 B
cdn.optoutadvertising.com/script/sf/ext.js	0.0 ms	0 B
content3.nrc.nl/script/viewability.js	0.0 ms	0 B

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.nmt-item__image-wrapper > figure.responsive-figure > picture > img `div.nmt-item__image-wrapper > figure.responsive-figure > picture > img`	/66GEIfdeYiIs4fHvdRqq-NZPFdg=/640x384/smart/filters:no_up...	67.5 KiB	59.1 KiB
div.nmt-item__image-wrapper > figure.responsive-figure > picture > img `div.nmt-item__image-wrapper > figure.responsive-figure > picture > img`	/6W5m80s1fbgYfp-ajmLzB4YHmOg=/640x384/smart/filters:no_up...	64.3 KiB	55.9 KiB
div.nmt-item__image-wrapper > figure.responsive-figure > picture > img `div.nmt-item__image-wrapper > figure.responsive-figure > picture > img`	/YwsdVI2fav3Hx97cujMnSR9dnug=/640x384/smart/filters:no_up...	63.6 KiB	55.1 KiB
div.nmt-item__image-wrapper > figure.responsive-figure > picture > img `div.nmt-item__image-wrapper > figure.responsive-figure > picture > img`	/Ugv_Jb9FZ4KJa2dlIrUJqOpM43g=/640x384/smart/filters:no_up...	50.7 KiB	42.2 KiB
div.nmt-item__image-wrapper > figure.responsive-figure > picture > img `div.nmt-item__image-wrapper > figure.responsive-figure > picture > img`	/OCQjHCqH_b038WptE8F2Lv2fRCQ=/640x384/smart/filters:no_up...	50.1 KiB	41.7 KiB
div.nmt-item__image-wrapper > figure.responsive-figure > picture > img `div.nmt-item__image-wrapper > figure.responsive-figure > picture > img`	/ycOfe3rDc4fzK-_kS38DOdDwgb4=/640x384/smart/filters:no_up...	54.2 KiB	34.1 KiB
div.nmt-item__image-wrapper > figure.responsive-figure > picture > img `div.nmt-item__image-wrapper > figure.responsive-figure > picture > img`	/WvAx1ITuRuUiaxIfLKC0QZWVKzU=/640x384/smart/filters:no_up...	40.6 KiB	32.2 KiB
div.nmt-item__image-wrapper > figure.responsive-figure > picture > img `div.nmt-item__image-wrapper > figure.responsive-figure > picture > img`	/c0yHXjen48LOgYWrYh69lkuHSno=/0x2:1920x1154/640x384/smart...	39.9 KiB	31.5 KiB
div.nmt-item__image-wrapper > figure.responsive-figure > picture > img `div.nmt-item__image-wrapper > figure.responsive-figure > picture > img`	/m6nDNCh-1M_8wK0PvY3HxuQfuKY=/640x384/smart/filters:no_up...	30.1 KiB	23.8 KiB
div.nmt-item__image-wrapper > figure.responsive-figure > picture > img `div.nmt-item__image-wrapper > figure.responsive-figure > picture > img`	/AtOHBnGx2VPQWa22i4RfePiic1U=/640x384/smart/filters:no_up...	43.3 KiB	23.2 KiB
div.nmt-item__image-wrapper > figure.responsive-figure > picture > img `div.nmt-item__image-wrapper > figure.responsive-figure > picture > img`	/06EifwYSiT452ri-Kvf-PLYoiRs=/640x384/smart/filters:no_up...	23.2 KiB	18.3 KiB
div.nmt-item__image-wrapper > figure.responsive-figure > picture > img `div.nmt-item__image-wrapper > figure.responsive-figure > picture > img`	/-HcOTgovjNwy2jtrYAafToOtH_g=/640x384/smart/filters:no_up...	35.4 KiB	17.7 KiB
div.nmt-item__image-wrapper > figure.responsive-figure > picture > img `div.nmt-item__image-wrapper > figure.responsive-figure > picture > img`	/I57VLQZqjq6qWwsD2ZxGgy7r1MM=/0x82:5892x3617/640x384/smar...	20.8 KiB	16.4 KiB
div.nmt-item__image-wrapper > figure.responsive-figure > picture > img `div.nmt-item__image-wrapper > figure.responsive-figure > picture > img`	/-i4B3fO8tgxuulp_G33CUeLD4q0=/640x384/smart/filters:no_up...	31.3 KiB	15.6 KiB
div.nmt-item__image-wrapper > figure.responsive-figure > picture > img `div.nmt-item__image-wrapper > figure.responsive-figure > picture > img`	/MLN735lqCETFx-jD0QiWRKgKtO8=/640x384/smart/filters:no_up...	16.6 KiB	13.1 KiB
a.photo-articles-gtm-click > figure.image > picture.photo-articles-gtm-click > img.photo-articles-gtm-click `a.photo-articles-gtm-click > figure.image > picture.photo-articles-gtm-click > img.photo-articles-gtm-click`	/eNtBb2TkBejUDMtm6fqQavGb1Tk=/160x96/smart/filters:no_ups...	8.1 KiB	5.6 KiB
a.photo-articles-gtm-click > figure.image > picture.photo-articles-gtm-click > img.photo-articles-gtm-click `a.photo-articles-gtm-click > figure.image > picture.photo-articles-gtm-click > img.photo-articles-gtm-click`	/3HbiHUOEP-RVOy3T6nwiPZOLt14=/160x96/smart/filters:no_ups...	7.1 KiB	4.6 KiB

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

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

Why this matters

Performance issues directly impact user engagement and conversion rates.

Estimated savings: 683 ms

URL	Time Spent
nrc.nl/	683 ms
www.nrc.nl/	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
NRC - Nieuws, achtergronden en onderzoeksjournalistiek ENERGIEMAATREGELEN Kabin… `body.indexpage > main#main-content`	0.815
Laatste nieuws 22:08 ASIEL Opnieuw onrust in Loosdrecht, rechter oordeelt dat a… `div.nmt-layout > div.nmt-layout__sidebar > div > div.timed-articles`	0.070
NRC - Nieuws, achtergronden en onderzoeksjournalistiek ENERGIEMAATREGELEN Kabin… `body.indexpage > main#main-content`	0.060
NRC - Nieuws, achtergronden en onderzoeksjournalistiek ENERGIEMAATREGELEN Kabin… `body.indexpage > main#main-content`	0.049
NRC - Nieuws, achtergronden en onderzoeksjournalistiek ENERGIEMAATREGELEN Kabin… `body.indexpage > main#main-content`	0.003
div.block__news__inner > div.nmt-layout > div.nmt-layout__sidebar > div.native-ad-item-holder `div.block__news__inner > div.nmt-layout > div.nmt-layout__sidebar > div.native-ad-item-holder`	0.002
Abonneren Podcasts Digitale krant `header.header > div.header__main > div.header__inner-container > div.header__buttons`	0.002
Binnenland Buitenland Economie Den Haag Cultuur Wetenschap Opinie Boeken Leven … `div.header__sections-and-selections__inner > div.header__sections-bar > div.header__sections-bar__inner > ul`	0.000

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

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	1.0 s
Other	673 ms
Style & Layout	406 ms
Rendering	225 ms
Script Parsing & Compilation	196 ms
Parse HTML & CSS	48 ms
Garbage Collection	24 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
The page has an unload handler in the main frame.	Actionable
The page has an unload handler in a sub frame.	Actionable

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

Why this matters

Performance issues directly impact user engagement and conversion rates.

Estimated savings: 0.0 ms 20.9 KiB

URL	Transfer Size	Est Savings
assets.nrc.nl/static/front/css/split/paywall.6b081e5b3.css	11.1 KiB	10.7 KiB
assets.nrc.nl/static/front/css/main.11aa071ef.css	13.0 KiB	10.2 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 619.5 KiB

URL	Transfer Size	Est Savings
prod-nrcm.mhtr.be/public/tr/tracker.min.js	158.8 KiB	113.2 KiB
assets.nrc.nl/static/front/js/main.db164c9ed.js	118.5 KiB	75.7 KiB
/sdk/22ecd6bfac93de604efec0b75b2c796ee1675f92/modern/sdk....	100.5 KiB	63.4 KiB
assets.nrc.nl/static/front/components/js/dmt-icon.2405b9fc1.js	89.4 KiB	63.1 KiB
load.sst.nrc.nl/gtag/js?id=G-Q3L8E2PF4V&cx=c&gtm=4e64k0	161.5 KiB	61.3 KiB
load.sst.nrc.nl/kxlupzzx.js?st=KKRPPB	166.0 KiB	45.2 KiB
script.hotjar.com/survey-v2.8b9993fd273bc1f4ea37.js	60.6 KiB	34.8 KiB
script.hotjar.com/survey-v2.8b9993fd273bc1f4ea37.js	60.6 KiB	34.8 KiB
script.hotjar.com/survey-v2.8b9993fd273bc1f4ea37.js	60.6 KiB	34.8 KiB
script.hotjar.com/survey-v2.8b9993fd273bc1f4ea37.js	60.6 KiB	34.8 KiB
script.hotjar.com/modules.6a0f3932cb1341a35c18.js	56.1 KiB	34.6 KiB
assets.nrc.nl/static/front/js/vendor.0677b1b4d.js	49.3 KiB	23.8 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.


a.podcast-index__card-item > aside > picture > img `a.podcast-index__card-item > aside > picture > img`
a.podcast-index__card-item > aside > picture > img `a.podcast-index__card-item > aside > picture > img`
a.podcast-index__card-item > aside > picture > img `a.podcast-index__card-item > aside > picture > img`
a.podcast-index__card-item > aside > picture > img `a.podcast-index__card-item > aside > picture > img`
a.podcast-index__card-item > aside > picture > img `a.podcast-index__card-item > aside > picture > img`
a.podcast-index__card-item > aside > picture > img `a.podcast-index__card-item > aside > picture > img`
a.podcast-index__card-item > aside > picture > img `a.podcast-index__card-item > aside > picture > img`

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

●Optimize DOM size

●Font display

●LCP breakdown

●Modern HTTP

●Optimize viewport for mobile

●Minify CSS

●Minify JavaScript

●Avoids enormous network payloads Total size was 2,363 KiB

●User Timing marks and measures 8 user timings

●JavaScript execution time 1.1 s

●Avoid long main-thread tasks 8 long tasks found

●Avoid non-composited animations 1 animated element found

●Network Requests

●Network Round Trip Times 250 ms

●Server Backend Latencies 180 ms

●Tasks

●Diagnostics

●Metrics

●Screenshot Thumbnails

●Final Screenshot

●Script Treemap Data

●Resources Summary

●Initial server response time was short Root document took 170 ms

○INP breakdown

Accessibility

These checks highlight opportunities to improve the accessibility of your web app. Automatic detection can only detect a subset of issues and does not guarantee the accessibility of your web app, so manual testing is also encouraged.

Names and labels

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
div.flexfloat-wrapper > div.flexfloat > div.native-slider__container > button.native-slider__button `div.flexfloat-wrapper > div.flexfloat > div.native-slider__container > button.native-slider__button`
div.flexfloat-wrapper > div.flexfloat > div.native-slider__container > button.native-slider__button `div.flexfloat-wrapper > div.flexfloat > div.native-slider__container > button.native-slider__button`

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
ASIEL `li.timed-articles__item > a > div.timed-articles__title-wrapper > h6.timed-articles__flag`
ALGERIJE `li.timed-articles__item > a > div.timed-articles__title-wrapper > h6.timed-articles__flag`
SCHIETPARTIJ `li.timed-articles__item > a > div.timed-articles__title-wrapper > h6.timed-articles__flag`
RECHTSZAAK `li.timed-articles__item > a > div.timed-articles__title-wrapper > h6.timed-articles__flag`
GEWELD `li.timed-articles__item > a > div.timed-articles__title-wrapper > h6.timed-articles__flag`
ANALYSE ASIELDEBAT `li.timed-articles__item > a > div.timed-articles__title-wrapper > h6.timed-articles__flag`
ANALYSE `a > div.timed-articles__title-wrapper > h6.timed-articles__flag > strong`
STRAAT VAN HORMUZ `li.timed-articles__item > a > div.timed-articles__title-wrapper > h6.timed-articles__flag`
OEKRAÏNE `li.timed-articles__item > a > div.timed-articles__title-wrapper > h6.timed-articles__flag`
22 apr 2026 `a.podcast-index__card-item > section > footer > span`
22 apr 2026 `a.podcast-index__card-item > section > footer > span`
22 apr 2026 `a.podcast-index__card-item > section > footer > span`
Volg `div.block__header__inner-bis > div.follow-topic > button.follow-button > span`
Volg `div.block__header__inner-bis > div.follow-topic > button.follow-button > span`

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
ENERGIEMAATREGELEN `div.nmt-item__inner > a.nmt-item__link > header.nmt-item__content > h6.nmt-item__flag`
ASIEL `div.nmt-item__inner > a.nmt-item__link > header.nmt-item__content > h6.nmt-item__flag`
BLOG AMERIKAANSE POLITIEK `div#item211367 > div.nmt-item__inner > header.nmt-item__content > h6.nmt-item__flag`
TOBACCO AND VAPES BILL `div.nmt-item__inner > a.nmt-item__link > header.nmt-item__content > h6.nmt-item__flag`
AANSLUITSTOP `div.nmt-item__inner > a.nmt-item__link > header.nmt-item__content > h6.nmt-item__flag`
ANALYSE ASIELDEBAT `div.nmt-item__inner > a.nmt-item__link > header.nmt-item__content > h6.nmt-item__flag`
STRAAT VAN HORMUZ `div.nmt-item__inner > a.nmt-item__link > header.nmt-item__content > h6.nmt-item__flag`
RECHTSZAAK `div.nmt-item__inner > a.nmt-item__link > header.nmt-item__content > h6.nmt-item__flag`
OPINIE CONSUMPTIEMAATSCHAPPIJ `div.nmt-item__inner > a.nmt-item__link > header.nmt-item__content > h6.nmt-item__flag`
TRANS RECHTEN `div.nmt-item__inner > a.nmt-item__link > header.nmt-item__content > h6.nmt-item__flag`
CULTUURDAGBOEK `div.nmt-item__inner > a.nmt-item__link > header.nmt-item__content > h6.nmt-item__flag`
RUBRIEK CLOSE-UP `div.nmt-item__inner > a.nmt-item__link > header.nmt-item__content > h6.nmt-item__flag`
ANALYSE VEILIGHEID `div.nmt-item__inner > a.nmt-item__link > header.nmt-item__content > h6.nmt-item__flag`
ESSAY EFTELING-KUNST `div.nmt-item__inner > a.nmt-item__link > header.nmt-item__content > h6.nmt-item__flag`
RECENSIE BLOEMEN \| ●● `div.nmt-item__inner > a.nmt-item__link > header.nmt-item__content > h6.nmt-item__flag`
INTERVIEW THEATERMAKERS DE HOE `div.nmt-item__inner > a.nmt-item__link > header.nmt-item__content > h6.nmt-item__flag`
ASIEL `li.timed-articles__item > a > div.timed-articles__title-wrapper > h6.timed-articles__flag`
BLOG AMERIKAANSE POLITIEK `li.photo-articles__item > a.photo-articles-gtm-click > div.photo-articles__title-wrapper > h6.photo-articles__flag`
COLUMN IN HET LAND `div.nmt-item__inner > a.nmt-item__link > header.nmt-item__content > h6.nmt-item__flag`
COLUMN CAROLIEN ROELANTS `div.nmt-item__inner > a.nmt-item__link > header.nmt-item__content > h6.nmt-item__flag`
OPINIE SCHOONHEIDSIDEALEN `div.nmt-item__inner > a.nmt-item__link > header.nmt-item__content > h6.nmt-item__flag`
JAPKE-D. DENKT MEE `div.nmt-item__inner > a.nmt-item__link > header.nmt-item__content > h6.nmt-item__flag`
KWALITEITSJOURNALISTIEK `div.nmt-item__inner > a.nmt-item__link > header.nmt-item__content > h6.nmt-item__flag`
THE ECONOMIST FREE EXCHANGE `div.nmt-item__inner > a.nmt-item__link > header.nmt-item__content > h6.nmt-item__flag`
THE ECONOMIST `div.nmt-item__inner > a.nmt-item__link > header.nmt-item__content > h6.nmt-item__flag`
THE ECONOMIST `div.nmt-item__inner > a.nmt-item__link > header.nmt-item__content > h6.nmt-item__flag`
INTERVIEW VERWEESDE ROOFKUNST `div.nmt-item__inner > a.nmt-item__link > header.nmt-item__content > h6.nmt-item__flag`
ANALYSE STEMMING ASIELWETTEN `div.nmt-item__inner > a.nmt-item__link > header.nmt-item__content > h6.nmt-item__flag`
RECHTSZAAK `div.nmt-item__inner > a.nmt-item__link > header.nmt-item__content > h6.nmt-item__flag`
ONTHEEMDING `div.nmt-item__inner > a.nmt-item__link > header.nmt-item__content > h6.nmt-item__flag`
PODCAST `a.podcast-index__card-item > section > header > h6.nmt-item__flag`
Onbehaarde Apen `a.podcast-index__card-item > section > footer > h5`
Vandaag `a.podcast-index__card-item > section > footer > h5`
Cocaïnekoorts `a.podcast-index__card-item > section > footer > h5`
Wereldzaken `a.podcast-index__card-item > section > footer > h5`
Haagse Zaken `a.podcast-index__card-item > section > footer > h5`
Het Uur `a.podcast-index__card-item > section > footer > h5`
Zo simpel is het niet – Stellinga & Schinkel over economie `a.podcast-index__card-item > section > footer > h5`
MUZIEKGIDS `div.nmt-item__inner > a.nmt-item__link > header.nmt-item__content > h6.nmt-item__flag`
THEATERGIDS `div.nmt-item__inner > a.nmt-item__link > header.nmt-item__content > h6.nmt-item__flag`
STREAMINGGIDS `div.nmt-item__inner > a.nmt-item__link > header.nmt-item__content > h6.nmt-item__flag`
BOEKENTIPS `div.nmt-item__inner > a.nmt-item__link > header.nmt-item__content > h6.nmt-item__flag`
SCHIETPARTIJ `div.nmt-item__inner > a.nmt-item__link > header.nmt-item__content > h6.nmt-item__flag`
GEWELD `div.nmt-item__inner > a.nmt-item__link > header.nmt-item__content > h6.nmt-item__flag`
REPORTAGE DOCENTENOPLEIDING FRIES `div.nmt-item__inner > a.nmt-item__link > header.nmt-item__content > h6.nmt-item__flag`
WET OPEN OVERHEID `div.nmt-item__inner > a.nmt-item__link > header.nmt-item__content > h6.nmt-item__flag`
NIEUWE PARTIJ `div.nmt-item__inner > a.nmt-item__link > header.nmt-item__content > h6.nmt-item__flag`
COLUMN IN HET LAND `div.nmt-item__inner > a.nmt-item__link > header.nmt-item__content > h6.nmt-item__flag`
ENERGIE `div.nmt-item__inner > a.nmt-item__link > header.nmt-item__content > h6.nmt-item__flag`
ANALYSE OORLOG IN IRAN `div.nmt-item__inner > a.nmt-item__link > header.nmt-item__content > h6.nmt-item__flag`
INTERVIEW HONGARIJE `div.nmt-item__inner > a.nmt-item__link > header.nmt-item__content > h6.nmt-item__flag`
ANALYSE EU EN ISRAËL `div.nmt-item__inner > a.nmt-item__link > header.nmt-item__content > h6.nmt-item__flag`
WAPENVERKOOP `div.nmt-item__inner > a.nmt-item__link > header.nmt-item__content > h6.nmt-item__flag`
ECONOMIEBLOG `div#item213021 > div.nmt-item__inner > header.nmt-item__content > h6.nmt-item__flag`
INTERVIEW `div.nmt-item__inner > a.nmt-item__link > header.nmt-item__content > h6.nmt-item__flag`
REPORTAGE `div.nmt-item__inner > a.nmt-item__link > header.nmt-item__content > h6.nmt-item__flag`
ENERGIECRISIS `div.nmt-item__inner > a.nmt-item__link > header.nmt-item__content > h6.nmt-item__flag`
CENSUUR `div.nmt-item__inner > a.nmt-item__link > header.nmt-item__content > h6.block--focus__flag`
FOTOGRAFIE `div.nmt-item__inner > a.nmt-item__link > header.nmt-item__content > h6.block--focus__flag`
ANALYSE KNVB-BEKER `div.nmt-item__inner > a.nmt-item__link > header.nmt-item__content > h6.nmt-item__flag`
REPORTAGE AMSTEL GOLD RACE `div.nmt-item__inner > a.nmt-item__link > header.nmt-item__content > h6.nmt-item__flag`
VOETBAL `div.nmt-item__inner > a.nmt-item__link > header.nmt-item__content > h6.nmt-item__flag`
INTERVIEW WIELERKLASSIEKER `div.nmt-item__inner > a.nmt-item__link > header.nmt-item__content > h6.nmt-item__flag`
DURF TE VRAGEN `div.nmt-item__inner > a.nmt-item__link > header.nmt-item__content > h6.nmt-item__flag`
ALLEDAAGSE WETENSCHAP `div.nmt-item__inner > a.nmt-item__link > header.nmt-item__content > h6.nmt-item__flag`
OPHEF `div.nmt-item__inner > a.nmt-item__link > header.nmt-item__content > h6.nmt-item__flag`
COLUMN ELLEN DECKWITZ `div.nmt-item__inner > a.nmt-item__link > header.nmt-item__content > h6.nmt-item__flag`
COLUMN MARJOLEINE DE VOS `div.nmt-item__inner > a.nmt-item__link > header.nmt-item__content > h6.nmt-item__flag`
MUSEUMGIDS `div.nmt-item__inner > a.nmt-item__link > header.nmt-item__content > h6.nmt-item__flag`
OPGEVOED `div.nmt-item__inner > a.nmt-item__link > header.nmt-item__content > h6.nmt-item__flag`
REACTIES OVERLIJDEN SONJA BAREND `div.nmt-item__inner > a.nmt-item__link > header.nmt-item__content > h6.nmt-item__flag`
TV-RECENSIE `div.nmt-item__inner > a.nmt-item__link > header.nmt-item__content > h6.nmt-item__flag`
PUBLIEKE OMROEP `div.nmt-item__inner > a.nmt-item__link > header.nmt-item__content > h6.nmt-item__flag`
TV-RECENSIE `div.nmt-item__inner > a.nmt-item__link > header.nmt-item__content > h6.nmt-item__flag`
CONNECTIES `div.nmt-item__inner > a.nmt-item__link > header.nmt-item__content > h6.nmt-item__flag`
KRUISWOORD `div.nmt-item__inner > a.nmt-item__link > header.nmt-item__content > h6.nmt-item__flag`
WOORDEN `div.nmt-item__inner > a.nmt-item__link > header.nmt-item__content > h6.nmt-item__flag`
CIJFERS `div.nmt-item__inner > a.nmt-item__link > header.nmt-item__content > h6.nmt-item__flag`
OPINIE LEZERSBRIEVEN `div.nmt-item__inner > a.nmt-item__link > header.nmt-item__content > h6.nmt-item__flag`
SPITSUUR `div.nmt-item__inner > a.nmt-item__link > header.nmt-item__content > h6.nmt-item__flag`
BERT SCHRIJFT EEN BOEK `div.nmt-item__inner > a.nmt-item__link > header.nmt-item__content > h6.nmt-item__flag`
IKJE `div.nmt-item__inner > a.nmt-item__link > header.nmt-item__content > h6.nmt-item__flag`
COLUMN FRITS ABRAHAMS `div.nmt-item__inner > a.nmt-item__link > header.nmt-item__content > h6.nmt-item__flag`

These are opportunities to improve keyboard navigation in your application.

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
div.nmt-layout__main > section.block--label-cultuur-uitgelicht > header.block__header > a.block__more-link `div.nmt-layout__main > section.block--label-cultuur-uitgelicht > header.block__header > a.block__more-link`
div.nmt-layout__main > section.block--label-opinie-columns > header.block__header > a.block__more-link `div.nmt-layout__main > section.block--label-opinie-columns > header.block__header > a.block__more-link`
div.nmt-layout__main > section.block--label-uit-the-economist > header.block__header > a.block__more-link `div.nmt-layout__main > section.block--label-uit-the-economist > header.block__header > a.block__more-link`
div.nmt-layout__main > section.block--label-beste-van-nrc > header.block__header > a.block__more-link `div.nmt-layout__main > section.block--label-beste-van-nrc > header.block__header > a.block__more-link`
div.nmt-layout__main > section.block--label-nieuwste-afleveringen-nrc-podcasts > header.block__header > a.block__more-link `div.nmt-layout__main > section.block--label-nieuwste-afleveringen-nrc-podcasts > header.block__header > a.block__more-link`
div.nmt-layout__main > section.block--label-uit-thuis > header.block__header > a.block__more-link `div.nmt-layout__main > section.block--label-uit-thuis > header.block__header > a.block__more-link`
div.nmt-layout__main > section.block--label-binnenland > header.block__header > a.block__more-link `div.nmt-layout__main > section.block--label-binnenland > header.block__header > a.block__more-link`
POLITIEK DEN HAAG `div.block__header__inner > div.block__header__inner-bis > h3.block__label > a`
div.nmt-layout__main > section.block--label-politiek-den-haag > header.block__header > a.block__more-link `div.nmt-layout__main > section.block--label-politiek-den-haag > header.block__header > a.block__more-link`
div.nmt-layout__main > section.block--label-buitenland > header.block__header > a.block__more-link `div.nmt-layout__main > section.block--label-buitenland > header.block__header > a.block__more-link`
div.nmt-layout__main > section.block--label-economie > header.block__header > a.block__more-link `div.nmt-layout__main > section.block--label-economie > header.block__header > a.block__more-link`
section.block--focus > div.block--focus__inner > header.block__header > a.block__more-link `section.block--focus > div.block--focus__inner > header.block__header > a.block__more-link`
section.block--focus > div.block--focus__inner > header.block__header > a.block__more-link `section.block--focus > div.block--focus__inner > header.block__header > a.block__more-link`
div.nmt-layout__main > section.block--label-de-puzzels-van-vandaag > header.block__header > a.block__more-link `div.nmt-layout__main > section.block--label-de-puzzels-van-vandaag > header.block__header > a.block__more-link`
CARRIÈRE `div.block__header__inner > div.block__header__inner-bis > h3.block__label > a`
div.nmt-layout__main > section.block--label-carriere > header.block__header > a.block__more-link `div.nmt-layout__main > section.block--label-carriere > header.block__header > a.block__more-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>`

●`[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

●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

●Document has a main landmark.

●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

○Deprecated ARIA roles were not used

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

○ARIA input fields have accessible names

○ARIA `meter` elements have accessible names

○ARIA `progressbar` elements have accessible names

○`[role]`s have all required `[aria-*]` attributes

○Elements with an ARIA `[role]` that require children to contain a specific `[role]` have all required children.

○`[role]`s are contained by their required parent element

○`[role]` values are valid

○Elements with the `role=text` attribute do not have focusable descendents.

○ARIA toggle fields have accessible names

○ARIA `tooltip` elements have accessible names

○ARIA `treeitem` elements have accessible names

○The page contains a heading, skip link, or landmark region

○`<dl>`'s contain only properly-ordered `<dt>` and `<dd>` groups, `<script>`, `<template>` or `<div>` elements.

○Definition list items are wrapped in `<dl>` elements

○ARIA IDs are unique

○No form fields have multiple labels

○`<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.

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
Unload event listeners are deprecated and will be removed.	prod-nrcm.mhtr.be/public/tr/tracker.min.js line 14, col 183846
AttributionReporting	/_/service_worker/63b0/sw_iframe.html?origin=https%3A%2F%...

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
load.sst.nrc.nl/kxlupzzx.js?st=KKRPPB
assets.nrc.nl/static/front/js/main.db164c9ed.js
prod-nrcm.mhtr.be/public/tr/tracker.min.js	prod-nrcm.mhtr.be/public/tr/tracker.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

●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 clickjacking with XFO or CSP

●Mitigate DOM-based XSS with Trusted Types

●Detected JavaScript libraries

○Redirects HTTP traffic to HTTPS

100

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.

○Structured data is valid

●Page isn’t blocked from indexing

●Document has a `<title>` element

●Document has a meta description

●Page has successful HTTP status code

●Links have descriptive text

●Links are crawlable

●robots.txt is valid

●Image elements have `[alt]` attributes

●Document has a valid `hreflang`

●Document has a valid `rel=canonical`