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

Audit breakdown by category with detailed findings.

56

Performance

Insights

Remove large, duplicate JavaScript modules from bundles to reduce unnecessary bytes consumed by network activity.

Why this matters

Performance issues directly impact user engagement and conversion rates.

Polyfills and transforms enable older browsers to use new JavaScript features. However, many aren't necessary for modern browsers. Consider modifying your JavaScript build process to not transpile Baseline features, unless you know you must support older browsers. Learn why most sites can deploy ES6+ code without transpiling

Why this matters

Performance issues directly impact user engagement and conversion rates.

3rd party code can significantly impact load performance. Reduce and defer loading of 3rd party code to prioritize your page's content.

Why this matters

Performance issues directly impact user engagement and conversion rates.

A long cache lifetime can speed up repeat visits to your page. Learn more about caching.

Why this matters

Performance issues directly impact user engagement and conversion rates.

RequestCache TTLTransfer Size
cdn.lbl.gov/stable/3/js/lblFullComponents.js?ver=5.0.228800.0 s83.2 KiB
cdn.lbl.gov/stable/3/assets/img/uc-logo.svg28800.0 s63.1 KiB
static.ctctcdn.com/js/signup-form-widget/current/signup-form-widget.min.js900.0 s37.2 KiB
cdn.lbl.gov/stable/3/assets/img/doe-logo.svg28800.0 s27.4 KiB
siteimproveanalytics.com/js/siteanalyze_8343.js86400.0 s41.1 KiB
cdn.lbl.gov/stable/3/js/lblHomesuite.js?ver=5.0.228800.0 s16.0 KiB
static.ctctcdn.com/js/signup-form-widget/current/signup-form-widget.css900.0 s5.7 KiB
cdn.lbl.gov/stable/3/css/global.css?ver=5.0.228800.0 s5.7 KiB
cdn.lbl.gov/stable/3/assets/icons/science-highlight.svg28800.0 s1.8 KiB
cdn.lbl.gov/stable/3/assets/icons/berkeley-lab-logo.svg28800.0 s1.8 KiB
cdn.lbl.gov/stable/3/assets/icons/article.svg28800.0 s1.3 KiB
cdn.lbl.gov/stable/3/assets/icons/job-title.svg28800.0 s1.3 KiB
cdn.lbl.gov/stable/3/assets/icons/search.svg28800.0 s1.1 KiB
cdn.lbl.gov/stable/3/assets/icons/threads.svg28800.0 s1.1 KiB
cdn.lbl.gov/stable/3/assets/icons/instagram.svg28800.0 s995 B
cdn.lbl.gov/stable/3/assets/icons/close.svg28800.0 s848 B
cdn.lbl.gov/stable/3/assets/icons/bluesky.svg28800.0 s651 B
cdn.lbl.gov/stable/3/assets/icons/arrow-right.svg28800.0 s644 B
cdn.lbl.gov/stable/3/assets/icons/caret-down.svg28800.0 s619 B
cdn.lbl.gov/stable/3/assets/icons/youtube.svg28800.0 s603 B
cdn.lbl.gov/stable/3/assets/icons/linkedin.svg28800.0 s592 B
cdn.lbl.gov/stable/3/assets/icons/facebook.svg28800.0 s588 B
cdn.lbl.gov/stable/3/assets/icons/x.svg28800.0 s562 B
cdn.lbl.gov/stable/3/assets/icons/square.svg28800.0 s462 B
/p.css?s=1&k=evi6dpc&ht=tk&f=12783.12784.12785.12786.1278...604800.0 s172 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:0.15626400000000001] map[node:map[boundingRect:map[bottom:841 height:655 left:0 right:1350 top:186 width:1350] lhId:page-7-DIV nodeLabel:div.container > div.wrapper path:1,HTML,1,BODY,2,DIV,2,DIV,0,DIV,0,DIV,0,MAIN,0,DIV,0,LBL-CONTAINER,a,#document-fragment,1,DIV,0,DIV selector:div.container > div.wrapper snippet:<div class="wrapper"> type:node] score:0.127394] map[node:map[boundingRect:map[bottom:5272 height:5086 left:0 right:1350 top:186 width:1350] lhId:page-10-DIV nodeLabel:DESI Completes Planned 3D Map of the Universe and Continues Exploring Scientist… path:1,HTML,1,BODY,2,DIV,2,DIV selector:body.home > div.page-wrap > div#page snippet:<div id="page" class="hfeed site container"> type:node] score:0.025373] map[node:map[boundingRect:map[bottom:841 height:575 left:0 right:650 top:266 width:650] lhId:page-9-DIV nodeLabel:View the article: null path:1,HTML,1,BODY,2,DIV,2,DIV,0,DIV,0,DIV,0,MAIN,0,DIV,0,LBL-CONTAINER,0,LBL-HS-HERO,a,#document-fragment,1,DIV,0,DIV,1,DIV selector:div.hs-hero > div.hs-hero__content > div.hs-hero__details snippet:<div class="hs-hero__details"> type:node] score:0.003497]]

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:52.48 source:map[column:419421 line:2 type:source-location url:https://cdn.lbl.gov/stable/3/js/lblFullComponents.js?ver=5.0.2 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:52.48 source:map[column:400247 line:1 type:source-location url:https://cdn.lbl.gov/stable/3/js/lblFullComponents.js?ver=5.0.2 urlProvider:network]] map[reflowTime:3.961 source:map[column:51474 line:0 type:source-location url:https://cdn.lbl.gov/stable/3/js/lblHomesuite.js?ver=5.0.2 urlProvider:network]] map[reflowTime:4.924 source:map[column:304446 line:1 type:source-location url:https://cdn.lbl.gov/stable/3/js/lblFullComponents.js?ver=5.0.2 urlProvider:network]] map[reflowTime:2.802 source:map[column:385385 line:1 type:source-location url:https://cdn.lbl.gov/stable/3/js/lblFullComponents.js?ver=5.0.2 urlProvider:network]] map[reflowTime:0.111 source:map[column:304712 line:1 type:source-location url:https://cdn.lbl.gov/stable/3/js/lblFullComponents.js?ver=5.0.2 urlProvider:network]] map[reflowTime:15.066 source:map[column:212739 line:1 type:source-location url:https://cdn.lbl.gov/stable/3/js/lblFullComponents.js?ver=5.0.2 urlProvider:network]] map[reflowTime:0.289 source:map[column:217448 line:1 type:source-location url:https://cdn.lbl.gov/stable/3/js/lblFullComponents.js?ver=5.0.2 urlProvider:network]]]

Reducing the download time of images can improve the perceived load time of the page and LCP. Learn more about optimizing image size

Why this matters

Performance issues directly impact user engagement and conversion rates.

URLResource SizeEst Savings
A fan of blue and white dots extending across a black background. div#post-wrap > lbl-container.cq-xxs > lbl-hs-hero > img.attachment-lbl-components-xl
/wp-content/uploads/2026/04/LBL_Top_1995x930px_DESI-Map-z...2.0 MiB1.8 MiB
Two scientists point at a figure on the computer. div.entry-content > lbl-container.cq-xxs > lbl-cta-image-text > img.attachment-lbl-components-md
www.lbl.gov/wp-content/uploads/2022/07/XBD201805-00340-001.jpeg503.6 KiB472.5 KiB
Blurred blue and red bokeh lights with a white logo spelling Genesis Mission ov… lbl-grid > lbl-featured-news > lbl-image > img.attachment-lbl-components-md
www.lbl.gov/wp-content/uploads/2025/11/GM-890x665px_Web.jpg128.1 KiB105.6 KiB
A wide view of an enhanced geothermal systems site. Various workers, trucks, tr… lbl-grid > lbl-featured-news > lbl-image > img.attachment-lbl-components-md
www.lbl.gov/wp-content/uploads/2026/04/Featured_1190px_fervo_9632-890x595-1.jpg109.0 KiB87.7 KiB
Bruno La Fontaine, Director of the Center for X-ray Optics (CXRO), speaks on ho… lbl-container.cq-xxs > lbl-grid > lbl-profile-card > img.attachment-lbl-components-sm
www.lbl.gov/wp-content/uploads/2025/08/330x330_XBD-202502-026-007.jpg43.2 KiB30.0 KiB
Headshot of Eva Schill. lbl-container.cq-xxs > lbl-grid > lbl-profile-card > img.attachment-lbl-components-sm
/wp-content/uploads/2025/05/EvaSchill_800x800px_XBD-20250...34.7 KiB21.5 KiB
Portrait of Katie Klymko, person with brown hair put into a braid wearing a gre… lbl-container.cq-xxs > lbl-grid > lbl-profile-card > img.attachment-lbl-components-sm
www.lbl.gov/wp-content/uploads/2025/08/330x330_XBD-202204-025-004.jpg34.3 KiB21.0 KiB

Optimize LCP by making the LCP image discoverable from the HTML immediately, and avoiding lazy-loading

Why this matters

Performance issues directly impact user engagement and conversion rates.

lhId: page-0-IMG
nodeLabel: A fan of blue and white dots extending across a black background.
path: 1,HTML,1,BODY,2,DIV,2,DIV,0,DIV,0,DIV,0,MAIN,0,DIV,0,LBL-CONTAINER,0,LBL-HS-HERO,1,IMG
selector: div#post-wrap > lbl-container.cq-xxs > lbl-hs-hero > img.attachment-lbl-components-xl
snippet: <img width="1995" height="930" src="https://www.lbl.gov/wp-content/uploads/2026/04/LBL_Top_1995x930px_DESI-Map…" class="attachment-lbl-components-xl size-lbl-components-xl" alt="A fan of blue and white dots extending across a black background." slot="media" decoding="async">

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.

URLTransfer SizeDuration
www.lbl.gov/wp-includes/js/dist/block-editor.min.js?ver=addf558a422e2ee57920258.4 KiB245 ms
www.lbl.gov/wp-includes/js/dist/components.min.js?ver=0d72a218dfea8f6f442f241.1 KiB204 ms
www.lbl.gov/wp-includes/js/dist/editor.min.js?ver=e94186146898a6d39837114.8 KiB123 ms
www.lbl.gov/wp-includes/js/dist/wordcount.min.js?ver=c5b97f11206928ea91301.3 KiB
www.lbl.gov/wp-includes/js/dist/viewport.min.js?ver=f07b4909c08cfe9de4e21.0 KiB
/wp-includes/js/dist/server-side-render.min.js?ver=7db247...1.6 KiB
www.lbl.gov/wp-includes/js/dist/plugins.min.js?ver=039ed87b5b9f7036ceee1.9 KiB
www.lbl.gov/wp-includes/js/dist/patterns.min.js?ver=4131f04a041db58120d87.4 KiB
www.lbl.gov/wp-includes/js/dist/media-utils.min.js?ver=c66754bed5498afe70503.7 KiB
www.lbl.gov/wp-includes/js/dist/core-data.min.js?ver=15baadfe6e137418807221.3 KiB
www.lbl.gov/wp-includes/js/dist/token-list.min.js?ver=cfdf635a436c3953a965647 B
www.lbl.gov/wp-includes/js/dist/style-engine.min.js?ver=7c6fcedc37dadafb8a812.1 KiB
www.lbl.gov/wp-includes/js/dist/preferences.min.js?ver=2ca086aed510c242a1ed2.9 KiB
/wp-includes/js/dist/preferences-persistence.min.js?ver=e...2.1 KiB
www.lbl.gov/wp-includes/js/dist/commands.min.js?ver=cac8f4817ab7cea0ac4916.6 KiB
www.lbl.gov/wp-includes/js/dist/notices.min.js?ver=f62fbf15dcc23301922f1007 B
cdn.lbl.gov/stable/3/js/lblFullComponents.js?ver=5.0.283.2 KiB282 ms
www.lbl.gov/wp-includes/js/dist/date.min.js?ver=795a56839718d3ff7eae41.0 KiB
/wp-includes/js/dist/keyboard-shortcuts.min.js?ver=fbc45a...1.4 KiB
www.lbl.gov/wp-includes/js/dist/api-fetch.min.js?ver=3a4d9af2b423048b0dee2.5 KiB
www.lbl.gov/wp-includes/js/dist/url.min.js?ver=9e178c9516d1222dc8343.8 KiB
www.lbl.gov/wp-includes/js/dist/blocks.min.js?ver=57eca4d23daac7159d8854.1 KiB123 ms
cdn.lbl.gov/stable/3/js/lblHomesuite.js?ver=5.0.216.0 KiB81 ms
cdn.lbl.gov/stable/3/css/global.css?ver=5.0.25.7 KiB214 ms
www.lbl.gov/wp-includes/js/dist/vendor/moment.min.js?ver=2.30.119.3 KiB
www.lbl.gov/wp-includes/js/dist/primitives.min.js?ver=0b5dcc337aa7cbf75570917 B
www.lbl.gov/wp-includes/js/dist/dom.min.js?ver=26edef3be6483da3de2e4.8 KiB
www.lbl.gov/wp-includes/js/dist/warning.min.js?ver=d69bc18c456d01c11d5a295 B
www.lbl.gov/wp-includes/js/dist/rich-text.min.js?ver=5bdbb44f3039529e364512.4 KiB
www.lbl.gov/wp-includes/js/dist/shortcode.min.js?ver=0b3174183b858f2df3201.5 KiB
www.lbl.gov/wp-includes/js/dist/a11y.min.js?ver=cb460b4676c94bd228ed912 B
www.lbl.gov/wp-includes/js/dist/html-entities.min.js?ver=e8b78b18a162491d5e5f562 B
www.lbl.gov/wp-includes/js/dist/dom-ready.min.js?ver=f77871ff7694fffea381398 B
www.lbl.gov/wp-includes/js/dist/redux-routine.min.js?ver=8bb92d45458b29590f533.0 KiB
www.lbl.gov/wp-includes/js/dist/compose.min.js?ver=7a9b375d8c19cf9d3d9b12.9 KiB82 ms
www.lbl.gov/wp-includes/js/dist/is-shallow-equal.min.js?ver=e0f9f1d78d83f5196979588 B
www.lbl.gov/wp-includes/js/dist/private-apis.min.js?ver=4f465748bda6247741391.0 KiB
www.lbl.gov/wp-includes/js/dist/keycodes.min.js?ver=34c8fb5e7a594a1c80371.4 KiB
www.lbl.gov/wp-includes/js/dist/priority-queue.min.js?ver=2d59d091223ee9a338381.6 KiB
www.lbl.gov/wp-includes/js/dist/deprecated.min.js?ver=e1f84915c5e8ae38964c515 B
www.lbl.gov/wp-includes/js/dist/element.min.js?ver=6a582b0c827fa25df3dd5.1 KiB
www.lbl.gov/wp-includes/js/dist/i18n.min.js?ver=c26c3dc7bed3667933752.3 KiB
www.lbl.gov/wp-includes/js/dist/escape-html.min.js?ver=6561a406d2d232a6fbd2594 B
www.lbl.gov/wp-includes/js/dist/data.min.js?ver=f940198280891b0b63188.9 KiB82 ms
www.lbl.gov/wp-includes/js/dist/vendor/react-dom.min.js?ver=18.3.1.141.6 KiB123 ms
www.lbl.gov/wp-includes/js/dist/vendor/react.min.js?ver=18.3.1.14.2 KiB
www.lbl.gov/wp-includes/js/dist/blob.min.js?ver=9113eed771d446f4a556623 B
www.lbl.gov/wp-includes/js/dist/autop.min.js?ver=9fb50649848277dd318d2.2 KiB
www.lbl.gov/wp-includes/js/dist/vendor/react-jsx-runtime.min.js?ver=18.3.1697 B
www.lbl.gov/wp-includes/js/dist/hooks.min.js?ver=dd5603f07f9220ed27f12.0 KiB
www.lbl.gov/wp-content/themes/lbl-theme/dist/bundle.css?ver=5.0.15.1 KiB
use.typekit.net/evi6dpc.css1.4 KiB
/wp-includes/js/dist/block-serialization-default-parser.m...1.2 KiB
use.typekit.net/evi6dpc.css?ver=5.0.11.4 KiB207 ms
/p.css?s=1&k=evi6dpc&ht=tk&f=12783.12784.12785.12786.1278...172 B240 ms

Consider setting font-display to swap or optional to ensure text is consistently visible. swap can be further optimized to mitigate layout shifts with font metric overrides.

Why this matters

Performance issues directly impact user engagement and conversion rates.

URLEst Savings
www.lbl.gov/wp-content/themes/lbl-theme/dist/802f7c7bf2678f253bea.woff220 ms
/af/b825af/0000000000000000000118b1/27/l?primer=7cdcb44be...10 ms
/af/2e6f07/000000000000000000011ce6/27/l?primer=7cdcb44be...10 ms
www.lbl.gov/wp-content/themes/lbl-theme/dist/d8a7ff3bddc1b6999fe9.woff210 ms
/af/9cb78a/0000000000000000000118ad/27/l?primer=7cdcb44be...5.0 ms

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: 692 ms
URLTime Spent
lbl.gov/429 ms
www.lbl.gov/263 ms
www.lbl.gov/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.

ElementLayout shift score
div.container > div.wrapper div.container > div.wrapper
0.127
DESI Completes Planned 3D Map of the Universe and Continues Exploring Scientist… body.home > div.page-wrap > div#page
0.025
View the article: null div.hs-hero > div.hs-hero__content > div.hs-hero__details
0.003

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

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: 490 ms 1008.2 KiB
URLTransfer SizeEst Savings
www.gstatic.com/recaptcha/releases/gTpTIWhbKpxADzTzkcabhXN4/recaptcha__en.js361.8 KiB242.2 KiB
www.lbl.gov/wp-includes/js/dist/block-editor.min.js?ver=addf558a422e2ee57920258.1 KiB213.2 KiB
www.lbl.gov/wp-includes/js/dist/components.min.js?ver=0d72a218dfea8f6f442f240.9 KiB193.3 KiB
www.lbl.gov/wp-includes/js/dist/editor.min.js?ver=e94186146898a6d39837114.6 KiB96.1 KiB
www.googletagmanager.com/gtm.js?id=GTM-M544LVV134.9 KiB63.9 KiB
www.googletagmanager.com/gtag/js?id=G-9N26W4812N&cx=c&gtm=4e64h1157.8 KiB63.5 KiB
www.lbl.gov/wp-includes/js/dist/vendor/react-dom.min.js?ver=18.3.1.141.5 KiB36.0 KiB
www.lbl.gov/wp-includes/js/dist/blocks.min.js?ver=57eca4d23daac7159d8852.9 KiB35.7 KiB
static.ctctcdn.com/js/signup-form-widget/current/signup-form-widget.min.js36.7 KiB34.8 KiB
cdn.lbl.gov/stable/3/js/lblFullComponents.js?ver=5.0.282.9 KiB29.5 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.

URLTransfer Size
/wp-content/uploads/2026/04/LBL_Top_1995x930px_DESI-Map-z...2.0 MiB
www.lbl.gov/wp-content/uploads/2022/08/XBD-202204-023_009.jpeg567.3 KiB
www.lbl.gov/wp-content/uploads/2022/07/XBD201805-00340-001.jpeg504.3 KiB
/wp-content/uploads/2022/06/Capabilities-Landing_CTA-Modu...412.0 KiB
www.gstatic.com/recaptcha/releases/gTpTIWhbKpxADzTzkcabhXN4/recaptcha__en.js362.3 KiB
www.lbl.gov/wp-content/uploads/2022/07/XBD201504-00099.jpeg337.1 KiB
www.lbl.gov/wp-includes/js/dist/block-editor.min.js?ver=addf558a422e2ee57920258.4 KiB
www.lbl.gov/wp-includes/js/dist/components.min.js?ver=0d72a218dfea8f6f442f241.1 KiB
www.googletagmanager.com/gtag/js?id=G-9N26W4812N&cx=c&gtm=4e64h1157.8 KiB
www.googletagmanager.com/gtm.js?id=GTM-M544LVV135.3 KiB

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

●Optimize DOM size
●LCP breakdown
●Modern HTTP
●Optimize viewport for mobile
●Minify CSS
●Minify JavaScript
●Reduce unused CSS
●User Timing marks and measures 5 user timings
●JavaScript execution time 0.3 s
●Minimizes main-thread work 1.2 s
●Avoid long main-thread tasks 4 long tasks found
●Avoid non-composited animations 4 animated elements found
●Image elements have explicit `width` and `height`
●Page didn't prevent back/forward cache restoration
●Network Requests
●Network Round Trip Times 70 ms
●Server Backend Latencies 110 ms
●Tasks
●Diagnostics
●Metrics
●Screenshot Thumbnails
●Final Screenshot
●Script Treemap Data
●Resources Summary
●Initial server response time was short Root document took 50 ms
○INP breakdown
91

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

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
a.btn a.btn
a.btn a.btn

These are opportunities to improve the semantics of the controls in your application. This may enhance the experience for users of assistive technology, like a screen reader.

Best practices

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

Why this matters

Performance issues directly impact user engagement and conversion rates.

Failing Elements
Submit Search form.search-form > button.search-form__button
ARTICLE div.tags > ul > li > a
COSMIC FRONTIERS div.tags > ul > li > a

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
●Buttons have an accessible name
●Image elements have `[alt]` attributes
●Form elements have associated labels
●`[user-scalable="no"]` is not used in the `<meta name="viewport">` element and the `[maximum-scale]` attribute is not less than 5.
●ARIA attributes are used as specified for the element's role
●Elements 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.
●Lists contain only `<li>` elements and script supporting elements (`<script>` and `<template>`).
●List items (`<li>`) are contained within `<ul>`, `<ol>` or `<menu>` parent elements
●Heading elements appear in a sequentially-descending order
●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-hidden="true"]` elements do not contain focusable descendents
○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
○The document does not use `<meta http-equiv="refresh">`
○`<object>` elements have alternate text
○Select elements have associated label elements.
○Skip links are focusable.
○No element has a `[tabindex]` value greater than 0
○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.
77

Best Practices

Trust and Safety

All sites should be protected with HTTPS, even ones that don't handle sensitive data. This includes avoiding mixed content, where some resources are loaded over HTTP despite the initial request being served over HTTPS. HTTPS prevents intruders from tampering with or passively listening in on the communications between your app and your users, and is a prerequisite for HTTP/2 and many new web platform APIs. Learn more about HTTPS.

Why this matters

Performance issues directly impact user engagement and conversion rates.

Insecure URLRequest Resolution
www.lbl.gov/Allowed

General

Errors logged to the console indicate unresolved problems. They can come from network request failures and other browser concerns. Learn more about this errors in console diagnostic audit

Why this matters

Performance issues directly impact user engagement and conversion rates.

SourceDescription
www.lbl.gov/ line 1018, col 0
Access to fetch at 'https://lbl.cloudflareaccess.com/cdn-cgi/access/login/www.lbl.gov?kid=b2d6a25b529ec8df9a4352b85b5517bed8a1d92022ad242c844528a61e1bd6d0&meta=eyJ0eXAiOiJKV1QiLCJhbGciOiJSUzI1NiIsImtpZCI6IjA1YWU4ZmM4NjVkOWYxMGM2NmJhZmM2Mzg1OGJhZmI3MzliYjc0YzlkMGE2NzFlZTM5NDZhZjg1NjI3M2U5NmQifQ.eyJ0eXBlIjoibWV0YSIsImF1ZCI6ImIyZDZhMjViNTI5ZWM4ZGY5YTQzNTJiODViNTUxN2JlZDhhMWQ5MjAyMmFkMjQyYzg0NDUyOGE2MWUxYmQ2ZDAiLCJob3N0bmFtZSI6Ind3dy5sYmwuZ292IiwicmVkaXJlY3RfdXJsIjoiL3dwLWpzb24vd3AvdjIvdXNlcnMvbWU_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.RKOi2RXTkIbEGrhfZvBmfSQ8MFdxgvNrOEyHPG-K9FkoBEJiO1kUhLveA1nVZqwHOv-oL7Rwd27120K4H-q-AYxUIhOilDvcK3FFndsgg0ocfq1DKq6DEpktYP0PmDC3RoqtPVGssb8wZn5QPjknHkkrOAg0UdZT8MOPE-uNK3cK-gYIyy4EZOfoYyyrN8RtRmVW6nT7rqEZjwKwFeB4FkwhjlzidzVJMHF9KeuAbi7gUhJqx3j6d7uerFTMXWKQtlF29X33EmW2POJXdWEBv5NWd8j2R47KtxOuIuIQ3Ki05Rt7ST13UBx0Gub-KpI8_fCEmQvmr1zwpYgaUJf0RQ&redirect_url=%2Fwp-json%2Fwp%2Fv2%2Fusers%2Fme%3Fcontext%3Dedit%26_locale%3Duser' (redirected from 'https://www.lbl.gov/wp-json/wp/v2/users/me?context=edit&_locale=user') from origin 'https://www.lbl.gov' has been blocked by CORS policy: Response to preflight request doesn't pass access control check: No 'Access-Control-Allow-Origin' header is present on the requested resource.
/cdn-cgi/access/login/www.lbl.gov?kid=b2d6a25b529ec8df9a4...
Failed to load resource: net::ERR_FAILED
www.lbl.gov/
Object

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.

URLMap URL
www.lbl.gov/wp-includes/js/dist/date.min.js?ver=795a56839718d3ff7eae
www.lbl.gov/wp-includes/js/dist/components.min.js?ver=0d72a218dfea8f6f442f
www.lbl.gov/wp-includes/js/dist/block-editor.min.js?ver=addf558a422e2ee57920
www.lbl.gov/wp-content/themes/lbl-theme/dist/bundle.js?ver=5.0.1www.lbl.gov/wp-content/themes/lbl-theme/dist/bundle.js.map
static.ctctcdn.com/js/signup-form-widget/current/signup-form-widget.min.jsstatic.ctctcdn.com/js/signup-form-widget/current/signup-form-widget.min.js.map
●Avoids deprecated APIs
●Avoids third-party cookies
●Allows users to paste into input fields
●Avoids requesting the geolocation permission on page load
●Avoids requesting the notification permission on page load
●Displays images with correct aspect ratio
●Serves images with appropriate resolution
●Page has the HTML doctype
●Properly defines charset
●No issues in the `Issues` panel in Chrome Devtools
●Ensure CSP is effective against XSS attacks
●Use a strong HSTS policy
●Ensure proper origin isolation with COOP
●Mitigate DOM-based XSS with Trusted Types
●Detected JavaScript libraries
○Redirects HTTP traffic to HTTPS
○Mitigate clickjacking with XFO or CSP
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`

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