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.

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
cdn-ukwest.onetrust.com/scripttemplates/202507.1.0/otBannerSdk.js	86400.0 s	119.9 KiB
i.ytimg.com/vi_webp/X2ZSRWKTUVA/maxresdefault.webp	7200.0 s	52.6 KiB
/logos/b1267e56-9bec-4ebe-a985-519ebdee1430/1d68d9f9-4078...	86400.0 s	41.7 KiB
cse.google.com/cse.js?cx=015306828578951525741:c1yjx6kt0fa	0.0 ms	3.9 KiB
cdn-ukwest.onetrust.com/scripttemplates/otSDKStub.js	86400.0 s	9.1 KiB
/consent/e481ef75-0b7a-49f5-91f3-f91f339f73a3/OtAutoBlock.js	86400.0 s	7.0 KiB
cdn-ukwest.onetrust.com/logos/static/powered_by_logo.svg	86400.0 s	2.5 KiB
www.google.com/cse/static/style/look/v6/default.css	3000.0 s	1.2 KiB
cdn-ukwest.onetrust.com/logos/static/ot_close.svg	86400.0 s	648 B

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
/s/opensans/v44/memvYaGs126MiZpBA-UvWbX2vVnXBbObj2OVTS-mu...	55 ms
/s/sourcesanspro/v23/6xKydSBYKcSV-LCoeQqfX1RYOo3i54rwlxdu...	50 ms
fonts.gstatic.com/s/roboto/v48/KFO7CnqEu92Fr1ME7kSn66aGLdTylUAMa3yUBHMdazQ.woff2	50 ms
fonts.gstatic.com/s/roboto/v48/KFO7CnqEu92Fr1ME7kSn66aGLdTylUAMa3yUBA.woff2	45 ms
/s/sourcesanspro/v23/6xKydSBYKcSV-LCoeQqfX1RYOo3ig4vwlxdu...	40 ms
/s/opensans/v44/memtYaGs126MiZpBA-UFUIcVXSCEkx2cmqvXlWqWu...	40 ms
/s/sourcesanspro/v23/6xK3dSBYKcSV-LCoeQqfX1RYOo3qOK7lujVj...	30 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:6.35 source:map[column:22766 line:7 type:source-location url:https://cdn-ukwest.onetrust.com/scripttemplates/202507.1.0/otBannerSdk.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:65.807 source:map[type:text value:[unattributed]]] map[reflowTime:10.613 source:map[column:29825 line:4 type:source-location url:https://www.cambridgeenglish.org/assets/js/vendor/jquery/1.11.3/jquery-1.11.3.min.js urlProvider:network]] map[reflowTime:5.645 source:map[column:23526 line:4 type:source-location url:https://www.cambridgeenglish.org/assets/js/vendor/jquery/1.11.3/jquery-1.11.3.min.js urlProvider:network]] map[reflowTime:0.556 source:map[column:26812 line:3 type:source-location url:https://www.cambridgeenglish.org/assets/js/vendor/jquery/1.11.3/jquery-1.11.3.min.js urlProvider:network]] map[reflowTime:0.265 source:map[column:27179 line:3 type:source-location url:https://www.cambridgeenglish.org/assets/js/vendor/jquery/1.11.3/jquery-1.11.3.min.js urlProvider:network]] map[reflowTime:0.482 source:map[column:27372 line:3 type:source-location url:https://www.cambridgeenglish.org/assets/js/vendor/jquery/1.11.3/jquery-1.11.3.min.js urlProvider:network]] map[reflowTime:0.273 source:map[column:27448 line:3 type:source-location url:https://www.cambridgeenglish.org/assets/js/vendor/jquery/1.11.3/jquery-1.11.3.min.js urlProvider:network]] map[reflowTime:0.774 source:map[column:24862 line:3 type:source-location url:https://www.cambridgeenglish.org/assets/js/vendor/jquery/1.11.3/jquery-1.11.3.min.js urlProvider:network]] map[reflowTime:0.419 source:map[column:31266 line:1 type:source-location url:https://www.cambridgeenglish.org/assets/js/vendor/jquery/1.11.3/jquery-1.11.3.min.js urlProvider:network]] map[reflowTime:0.25 source:map[column:22211 line:0 type:source-location url:https://www.cambridgeenglish.org/js/jquery.fancybox--modified.js urlProvider:network]] map[reflowTime:0.217 source:map[column:28964 line:3 type:source-location url:https://www.cambridgeenglish.org/assets/js/vendor/jquery/1.11.3/jquery-1.11.3.min.js urlProvider:network]] map[reflowTime:3.21 source:map[column:280 line:386 type:source-location url:https://www.google.com/cse/static/element/dc329f57de078f5d/cse_element__en.js?usqp=CAM%3D urlProvider:network]] map[reflowTime:0.537 source:map[column:390 line:537 type:source-location url:https://www.google.com/cse/static/element/dc329f57de078f5d/cse_element__en.js?usqp=CAM%3D urlProvider:network]] map[reflowTime:4.268 source:map[column:282346 line:6 type:source-location url:https://cdn-ukwest.onetrust.com/scripttemplates/202507.1.0/otBannerSdk.js urlProvider:network]] map[reflowTime:2.082 source:map[column:282690 line:6 type:source-location url:https://cdn-ukwest.onetrust.com/scripttemplates/202507.1.0/otBannerSdk.js 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.

	URL	Resource Size	Est Savings
Two educators smiling outdoors, representing trusted teaching support `div.panel > div.panel__body > figure.article__media > img`	www.cambridgeenglish.org/Images/trust_english-trust_page_updates_journey.jpg	310.5 KiB	270.9 KiB
Top UK children’s books collection. `div.panel > div.panel__body > figure.article__media > img`	www.cambridgeenglish.org/Images/courses-and-materials-for-learning-english.jpg	175.7 KiB	139.4 KiB
Banner with where your world grows text. `div.drupal > div.hero > div.hero-image > img`	www.cambridgeenglish.org/Images/ce-banner.jpg	173.0 KiB	121.5 KiB
Woman with glasses in library. `div.panel > div.panel__body > figure.article__media > img`	www.cambridgeenglish.org/Images/world-shaped-by-research-and-insights.jpg	106.5 KiB	84.5 KiB
Girl with headphones using laptop. `div.panel > div.panel__body > figure.article__media > img`	www.cambridgeenglish.org/Images/girl-taking-online-exam.jpg	99.3 KiB	78.8 KiB
Responsive website design on devices. `div.panel > div.panel__body > figure.article__media > img`	www.cambridgeenglish.org/Images/digital-tools-for-better-learning.jpg	88.8 KiB	70.5 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-2-IMG

nodeLabel: Banner with where your world grows text.

path: 6,HTML,2,BODY,5,FORM,5,MAIN,0,DIV,0,DIV,0,DIV,0,DIV,0,DIV,0,DIV,0,IMG

selector: div.drupal > div.hero > div.hero-image > img

snippet: <img src="/Images/ce-banner.jpg" alt="Banner with where your world grows text.">

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

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
/consent/e481ef75-0b7a-49f5-91f3-f91f339f73a3/OtAutoBlock.js	7.0 KiB	265 ms
www.cambridgeenglish.org/assets/js/vendor/jquery/1.11.3/jquery-1.11.3.min.js	33.0 KiB
www.cambridgeenglish.org/js/jwplayer.js	25.1 KiB	80 ms
fonts.googleapis.com/css?family=Source+Sans+Pro:300,400,400i,600,600i,700	1.4 KiB	284 ms
cdn-ukwest.onetrust.com/scripttemplates/otSDKStub.js	9.1 KiB	57 ms
www.cambridgeenglish.org/assets/css/style.css?v=3.8	54.8 KiB	120 ms
www.cambridgeenglish.org/assets/js/vendor/modernizr/modernizr.custom.min.js	3.9 KiB
www.cambridgeenglish.org/assets/js/vendor/Site24x7/RUM1monitoring.js	589 B
www.cambridgeenglish.org/css/local-business.css?v=2.8	15.4 KiB
www.cambridgeenglish.org/css/local-publication.css?v=2.5	21.0 KiB

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

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: 200 ms 116.1 KiB

URL	Transfer Size	Est Savings
www.cambridgeenglish.org/assets/css/style.css?v=3.8	54.7 KiB	50.7 KiB
www.cambridgeenglish.org/css/local-publication.css?v=2.5	20.9 KiB	19.5 KiB
	22.4 KiB	19.5 KiB
www.cambridgeenglish.org/css/local-business.css?v=2.8	15.3 KiB	14.9 KiB
www.google.com/cse/static/element/dc329f57de078f5d/default_v6+en.css	11.9 KiB	11.5 KiB

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

Why this matters

Performance issues directly impact user engagement and conversion rates.

Estimated savings: 40 ms 611.1 KiB

URL	Transfer Size	Est Savings
www.gstatic.com/recaptcha/releases/gTpTIWhbKpxADzTzkcabhXN4/recaptcha__en.js	361.8 KiB	241.8 KiB
www.googletagmanager.com/gtm.js?id=GTM-NHCSV7	173.3 KiB	76.9 KiB
www.googletagmanager.com/gtag/js?id=G-RWH1WT5Q9J&cx=c&gtm=4e64k1h2	171.0 KiB	68.2 KiB
cdn-ukwest.onetrust.com/scripttemplates/202507.1.0/otBannerSdk.js	119.8 KiB	62.9 KiB
/assets/js/vendor/jquery-ui/1.11.4/jquery-ui.min.js?v=0.1	63.1 KiB	56.7 KiB
/cse/static/element/dc329f57de078f5d/cse_element__en.js?u...	102.7 KiB	52.5 KiB
cse.google.com/adsense/search/async-ads.js	43.3 KiB	31.5 KiB
www.cambridgeenglish.org/js/jwplayer.js	25.0 KiB	20.7 KiB

Minifying CSS files can reduce network payload sizes. Learn how to minify CSS.

Why this matters

Performance issues directly impact user engagement and conversion rates.

Estimated savings: 0.0 ms 10.0 KiB

URL	Transfer Size	Est Savings
www.cambridgeenglish.org/css/local-business.css?v=2.8	15.4 KiB	3.8 KiB
www.google.com/cse/static/element/dc329f57de078f5d/default_v6+en.css	12.0 KiB	3.3 KiB
www.cambridgeenglish.org/assets/css/print.css?v=0.4	3.9 KiB	2.9 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.youtube-nocookie.com/s/player/1bb6ee63/player_embed.vflset/en_US/base.js	471.9 KiB
www.youtube-nocookie.com/s/player/8456c9de/player_embed_es6.vflset/en_US/base.js	436.5 KiB
www.gstatic.com/recaptcha/releases/gTpTIWhbKpxADzTzkcabhXN4/recaptcha__en.js	362.4 KiB
www.cambridgeenglish.org/Images/trust_english-trust_page_updates_journey.jpg	312.0 KiB
www.cambridgeenglish.org/Images/promise-to-the-planet.jpg	282.3 KiB
www.cambridgeenglish.org/Images/cambridge-history-and-heritage.jpg	235.0 KiB
/s/_/ytembeds/_/js/k=ytembeds.base.en_US.-RE1iC8VNhI.es5....	202.7 KiB
www.cambridgeenglish.org/Images/courses-and-materials-for-learning-english.jpg	176.6 KiB
www.cambridgeenglish.org/Images/ce-banner.jpg	173.9 KiB
www.googletagmanager.com/gtm.js?id=GTM-NHCSV7	173.8 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.

	URL
Woman with glasses in library. `div.panel > div.panel__body > figure.article__media > img`	www.cambridgeenglish.org/Images/world-shaped-by-research-and-insights.jpg
Top UK children’s books collection. `div.panel > div.panel__body > figure.article__media > img`	www.cambridgeenglish.org/Images/courses-and-materials-for-learning-english.jpg
Girl with headphones using laptop. `div.panel > div.panel__body > figure.article__media > img`	www.cambridgeenglish.org/Images/girl-taking-online-exam.jpg
Responsive website design on devices. `div.panel > div.panel__body > figure.article__media > img`	www.cambridgeenglish.org/Images/digital-tools-for-better-learning.jpg
Cambridge sustainability logo over aerial view of green forest `div.panel > div.panel__body > figure.article__media > img`	www.cambridgeenglish.org/Images/promise-to-the-planet.jpg
Aerial view of University of Cambridge. `div.panel > div.panel__body > figure.article__media > img`	www.cambridgeenglish.org/Images/cambridge-history-and-heritage.jpg
Man and woman talking on a couch. `div.panel > div.panel__body > figure.article__media > img`	www.cambridgeenglish.org/Images/cambridge-customer-support.jpg
Banner with where your world grows text. `div.drupal > div.hero > div.hero-image > img`	www.cambridgeenglish.org/Images/ce-banner.jpg
Two educators smiling outdoors, representing trusted teaching support `div.panel > div.panel__body > figure.article__media > img`	www.cambridgeenglish.org/Images/trust_english-trust_page_updates_journey.jpg
div.drupal > div.hero > div.hero-image > img `div.drupal > div.hero > div.hero-image > img`	www.cambridgeenglish.org/Images/blue%20wave%20divider.jpg
monash-university `div.feature > div > div.logo-container > img`	www.cambridgeenglish.org/Images/Monash-University-logo.jpg
mcgill-logo `div.feature > div > div.logo-container > img`	www.cambridgeenglish.org/Images/McGill-logo.jpg
accenture-logo `div.feature > div > div.logo-container > img`	www.cambridgeenglish.org/Images/Accenture-logo.jpg
p+g-logo `div.feature > div > div.logo-container > img.center-logo`	www.cambridgeenglish.org/Images/P-and-G-logo.jpg
kings-college-logo `div.feature > div > div.logo-container > img`	www.cambridgeenglish.org/Images/Kings-College-London-logo.jpg
Cambridge University Press & Assessment `ul.footer_container__list > li.footer_container__list-item > a.link--external > img.image--small`	/Images/Cambridge_Press_Assessment_Landscape_Logo_RGB-280...
BSI Logo `ul.footer_container__list > li.footer_container__list-item > a.link--external > img.image--small`	www.cambridgeenglish.org/Images/bsi-logo-footer.png
ALTE logo `ul.footer_container__list > li.footer_container__list-item > a.link--external > img.image--small`	www.cambridgeenglish.org/Images/alte-logo-footer.png
English Profile logo `ul.footer_container__list > li.footer_container__list-item > a.link--external > img.image--small`	www.cambridgeenglish.org/Images/english-profile-logo-footer.png
English `div.header_wrap > p.logo > span.logo-text > img`	www.cambridgeenglish.org/Images/english-logo.svg

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

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

Why this matters

Performance issues directly impact user engagement and conversion rates.

Estimated savings: 290 ms

URL	Time Spent
cambridgeenglish.org/	290 ms
www.cambridgeenglish.org/	0.0 ms

●Time to Interactive 1.6 s

●Layout shift culprits

●Optimize DOM size

●LCP breakdown

●Modern HTTP

●Optimize viewport for mobile

●Max Potential First Input Delay 50 ms

●Minify JavaScript

●User Timing marks and measures 7 user timings

●JavaScript execution time 0.3 s

●Minimizes main-thread work 1.0 s

●Avoid non-composited animations 1 animated element found

●Page didn't prevent back/forward cache restoration

●Network Requests

●Network Round Trip Times 60 ms

●Server Backend Latencies 30 ms

●Tasks

●Diagnostics

●Metrics

●Screenshot Thumbnails

●Final Screenshot

●Script Treemap Data

●Resources Summary

●Initial server response time was short Root document took 30 ms

●Avoid large layout shifts 11 layout shifts found

○INP breakdown

○Avoid long main-thread tasks

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

Each ARIA `role` supports a specific subset of `aria-*` attributes. Mismatching these invalidates the `aria-*` attributes. Learn how to match ARIA attributes to their roles.

Why this matters

Performance issues directly impact user engagement and conversion rates.

Failing Elements
Main navigation HomeEducators and organisationsLearnersLearning & assessment pr… `body#anchor-top > form#ctl00 > header.header > div#js-navigation-id`

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

Screen reader users rely on frame titles to describe the contents of frames. Learn more about frame titles.

Why this matters

Performance issues directly impact user engagement and conversion rates.

Failing Elements
main#anchor-main > div > div > iframe `main#anchor-main > div > div > iframe`

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

Visible text labels that do not match the accessible name can result in a confusing experience for screen reader users. Learn more about accessible names.

Why this matters

Performance issues directly impact user engagement and conversion rates.

Failing Elements
Cookie notice `div#onetrust-group-container > div#onetrust-policy > div#onetrust-policy-text > a.ot-cookie-policy-link`

○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-hidden="true"]` is not present on the document `<body>`

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

●`[role]` values are valid

●`[aria-*]` attributes have valid values

●`[aria-*]` attributes are valid and not misspelled

●Buttons have an accessible name

●Image elements have `[alt]` attributes

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

●`[aria-hidden="true"]` elements do not contain focusable descendents

●Elements use only permitted ARIA attributes

●Background and foreground colors have a sufficient contrast ratio

●Document has a `<title>` element

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

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

●Links are distinguishable without relying on color.

●Links have a discernible name

●Lists contain only `<li>` elements and script supporting elements (`<script>` and `<template>`).

●List items (`<li>`) are contained within `<ul>`, `<ol>` or `<menu>` parent elements

●No element has a `[tabindex]` value greater than 0

●Touch targets have sufficient size and spacing.

●Heading elements appear in a sequentially-descending order

●Skip links are focusable.

●Document has a main landmark.

●Deprecated ARIA roles were not used

●Uses ARIA roles only on compatible elements

●Identical links have the same purpose.

○`[accesskey]` values are unique

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

○ARIA input fields have accessible names

○ARIA `meter` elements have accessible names

○ARIA `progressbar` elements have accessible names

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

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

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

○ARIA toggle fields have accessible names

○ARIA `tooltip` elements have accessible names

○ARIA `treeitem` elements have accessible names

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

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

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

○ARIA IDs are unique

○No form fields have multiple labels

○`<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.

○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.

○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

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.

Source	Description
www.cambridgeenglish.org/assets/js/init.js?v=2.3	`TypeError: Cannot set properties of undefined (setting 'onclick') at https://www.cambridgeenglish.org/assets/js/init.js?v=2.3:1:23552`

●Uses HTTPS

●Avoids deprecated APIs

●Avoids third-party cookies

●Allows users to paste into input fields

●Avoids requesting the geolocation permission on page load

●Avoids requesting the notification permission on page load

●Displays images with correct aspect ratio

●Serves images with appropriate resolution

●Page has the HTML doctype

●Properly defines charset

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

●Ensure CSP is effective against XSS attacks

●Use a strong HSTS policy

●Ensure proper origin isolation with COOP

●Mitigate DOM-based XSS with Trusted Types

●Detected JavaScript libraries

●Page has valid source maps

○Redirects HTTP traffic to HTTPS

○Mitigate clickjacking with XFO or CSP

SEO

These checks ensure that your page is following basic search engine optimization advice. There are many additional factors Lighthouse does not score here that may affect your search ranking, including performance on Core Web Vitals. Learn more about Google Search Essentials.

Content Best Practices

Descriptive link text helps search engines understand your content. Learn how to make links more accessible.

Why this matters

Performance issues directly impact user engagement and conversion rates.

Link destination	Link Text
www.cambridge.org/legal/cookies	More information

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

○Structured data is valid

●Page isn’t blocked from indexing

●Document has a `<title>` element

●Document has a meta description

●Page has successful HTTP status code

●Links are crawlable

●robots.txt is valid

●Image elements have `[alt]` attributes

●Document has a valid `hreflang`

●Document has a valid `rel=canonical`