Lighthouse Mobile
· 0 checks — Mobile Lighthouse audit -- Performance, Accessibility, Best Practices, and SEO category breakdown.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.
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
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.
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.
Performance issues directly impact user engagement and conversion rates.
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.
Performance issues directly impact user engagement and conversion rates.
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.
Performance issues directly impact user engagement and conversion rates.
| URL | Transfer Size | Duration |
|---|---|---|
| jestjs.io/assets/css/styles.a07fbb26.css | 27.7 KiB | 300 ms |
Reducing the download time of images can improve the perceived load time of the page and LCP. Learn more about optimizing image size
Performance issues directly impact user engagement and conversion rates.
| URL | Resource Size | Est Savings | |
|---|---|---|---|
Instagram div.blockContent > div.gridBlockV1 > a.logo-item > img | jestjs.io/img/logos/instagram.png | 55.2 KiB | 52.4 KiB |
Spotify div.blockContent > div.gridBlockV1 > a.logo-item > img | jestjs.io/img/logos/spotify.png | 38.8 KiB | 36.0 KiB |
Airbnb div.blockContent > div.gridBlockV1 > a.logo-item > img | jestjs.io/img/logos/airbnb.png | 31.8 KiB | 30.1 KiB |
Datadog's avatar div.opencollective > div.opencollective-avatars > a.sponsor-item > img.sponsor-avatar | images.opencollective.com/datadog/5301801/logo.png | 13.2 KiB | 10.7 KiB |
The New York Times div.blockContent > div.gridBlockV1 > a.logo-item > img | jestjs.io/img/logos/nyt.png | 10.6 KiB | 8.5 KiB |
Airbnb's avatar div.opencollective > div.opencollective-avatars > a.sponsor-item > img.sponsor-avatar | images.opencollective.com/airbnb/d327d66/logo.png | 7.2 KiB | 4.6 KiB |
These insights are also available in the Chrome DevTools Performance Panel - record a trace to view more detailed information.
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.
Performance issues directly impact user engagement and conversion rates.
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.
Performance issues directly impact user engagement and conversion rates.
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.
Performance issues directly impact user engagement and conversion rates.
| URL | Transfer Size | Est Savings |
|---|---|---|
| jestjs.io/assets/css/styles.a07fbb26.css | 27.5 KiB | 17.9 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.
Performance issues directly impact user engagement and conversion rates.
| URL | Transfer Size | Est Savings |
|---|---|---|
| www.googletagmanager.com/gtag/js?id=G-9V0LCYENMT&cx=c>m=4e6411 | 144.3 KiB | 62.7 KiB |
| www.googletagmanager.com/gtag/js?id=UA-44373548-17 | 123.4 KiB | 62.6 KiB |
| jestjs.io/assets/js/main.17432a57.js | 140.3 KiB | 32.9 KiB |
Consider reducing the time spent parsing, compiling, and executing JS. You may find delivering smaller JS payloads helps with this. Learn how to reduce Javascript execution time.
Performance issues directly impact user engagement and conversion rates.
| URL | Total CPU Time | Script Evaluation | Script Parse |
|---|---|---|---|
| jestjs.io/ | 2.6 s | 27 ms | 3.9 ms |
| jestjs.io/assets/js/main.17432a57.js | 1.2 s | 1.0 s | 72 ms |
| Unattributable | 524 ms | 80 ms | 0.0 ms |
| www.googletagmanager.com/gtag/js?id=UA-44373548-17 | 277 ms | 227 ms | 49 ms |
| www.googletagmanager.com/gtag/js?id=G-9V0LCYENMT&cx=c>m=4e6411 | 214 ms | 154 ms | 58 ms |
| jestjs.io/assets/js/8155.4644b154.js | 74 ms | 59 ms | 15 ms |
| www.google-analytics.com/analytics.js | 72 ms | 56 ms | 7.0 ms |
Consider reducing the time spent parsing, compiling and executing JS. You may find delivering smaller JS payloads helps with this. Learn how to minimize main-thread work
Performance issues directly impact user engagement and conversion rates.
| Category | Time Spent |
|---|---|
| Script Evaluation | 1.7 s |
| Other | 1.2 s |
| Style & Layout | 1.1 s |
| Rendering | 872 ms |
| Script Parsing & Compilation | 219 ms |
| Garbage Collection | 38 ms |
| Parse HTML & CSS | 36 ms |
Set an explicit width and height on image elements to reduce layout shifts and improve CLS. Learn how to set image dimensions
Performance issues directly impact user engagement and conversion rates.
| URL | |
|---|---|
Airbnb div.blockContent > div.gridBlockV1 > a.logo-item > img | jestjs.io/img/logos/airbnb.png |
Facebook div.blockContent > div.gridBlockV1 > a.logo-item > img | jestjs.io/img/logos/facebook.png |
Instagram div.blockContent > div.gridBlockV1 > a.logo-item > img | jestjs.io/img/logos/instagram.png |
The New York Times div.blockContent > div.gridBlockV1 > a.logo-item > img | jestjs.io/img/logos/nyt.png |
Spotify div.blockContent > div.gridBlockV1 > a.logo-item > img | jestjs.io/img/logos/spotify.png |
OpenJS Foundation Logo div.footer__bottom > div.margin-bottom--sm > a.footerLogoLink_tutC > img.footer__logo | jestjs.io/img/openjs_foundation-logo-horizontal-color-dark_background.svg |
Twitter div.blockContent > div.gridBlockV1 > a.logo-item > img | jestjs.io/img/logos/twitter.png |
More information about the performance of your application. These numbers don't directly affect the Performance score.
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.
Contrast
Low-contrast text is difficult or impossible for many users to read. Learn how to provide sufficient color contrast.
Performance issues directly impact user engagement and conversion rates.
| Failing Elements |
|---|
JEST div.navbar__inner > div.theme-layout-navbar-left > a.navbar__brand > b.navbar__title |
PASS div.jest-card-hitslop > div.jest-card > div.jest-card-front > div.jest-card-label |
JEST div.jest-card-hitslop > div.jest-card > div.jest-card-front > div.jest-card-label |
PASS div.jest-card-hitslop > div.jest-card > div.jest-card-front > div.jest-card-label |
zero config h2 > div > span > p |
snapshots h2 > div > span > p |
isolated h2 > div > span > p |
great api h2 > div > span > p |
FAST AND SAFE h2 > div > span > p |
CODE COVERAGE h2 > div > span > p |
--coverage span > p > a > code |
Mock Functions div > span > p > a |
GREAT EXCEPTIONS h2 > div > span > p |
toBeCloseTo div.blockElement > div.blockContent > p.buttons-wrapper > a.button |
toEqual div.blockElement > div.blockContent > p.buttons-wrapper > a.button |
toStrictEqual div.blockElement > div.blockContent > p.buttons-wrapper > a.button |
toHaveProperty div.blockElement > div.blockContent > p.buttons-wrapper > a.button |
toMatchSnapshot div.blockElement > div.blockContent > p.buttons-wrapper > a.button |
toThrowError div.blockElement > div.blockContent > p.buttons-wrapper > a.button |
PHILOSOPHY div.wrapperV1 > div.blockElement > div.blockContent > h2 |
Jest and Delightful JavaScript Testing div > span > p > a |
Building High-Quality JavaScript Tools div > span > p > a |
Jest as a Platform div > span > p > a |
OPEN COLLECTIVE div.wrapperV1 > div.yellow > div.blockContent > h2 |
gold sponsors div.yellow > div.blockContent > div.opencollective > h3 |
featured sponsors div.yellow > div.blockContent > div.opencollective > h3 |
Join 600+ donors div.blockContent > div.opencollective > p > a |
opencollective.com div.blockContent > div.opencollective > p > a |
WHO USES JEST? div.wrapperV1 > div.yellow > div.blockContent > h2 |
100m+ million div > span > p > a |
15,000,000 div > span > p > a |
OpenJS Foundation div.footer__bottom > div.footer__copyright > p > a |
OpenJS Foundation div.footer__bottom > div.footer__copyright > p > a |
OpenJS Foundation div.footer__bottom > div.footer__copyright > p > a |
Trademark Policy div.footer__bottom > div.footer__copyright > p > a |
Trademark List div.footer__bottom > div.footer__copyright > p > a |
list of OpenJS Foundation trademarks div.footer__bottom > div.footer__copyright > p > a |
The OpenJS Foundation div.footer__bottom > div.footer__copyright > p > a |
Terms of Use div.footer__bottom > div.footer__copyright > p > a |
Privacy Policy div.footer__bottom > div.footer__copyright > p > a |
Bylaws div.footer__bottom > div.footer__copyright > p > a |
Code of Conduct div.footer__bottom > div.footer__copyright > p > a |
Trademark Policy div.footer__bottom > div.footer__copyright > p > a |
Trademark List div.footer__bottom > div.footer__copyright > p > a |
Cookie Policy div.footer__bottom > div.footer__copyright > p > a |
Low-contrast text is difficult or impossible for many users to read. Link text that is discernible improves the experience for users with low vision. Learn how to make links distinguishable.
Performance issues directly impact user engagement and conversion rates.
| Failing Elements |
|---|
OpenJS Foundation div.footer__bottom > div.footer__copyright > p > a |
OpenJS Foundation div.footer__bottom > div.footer__copyright > p > a |
OpenJS Foundation div.footer__bottom > div.footer__copyright > p > a |
Trademark Policy div.footer__bottom > div.footer__copyright > p > a |
Trademark List div.footer__bottom > div.footer__copyright > p > a |
list of OpenJS Foundation trademarks div.footer__bottom > div.footer__copyright > p > a |
These are opportunities to improve the legibility of your content.
Best practices
One main landmark helps screen reader users navigate a web page. Learn more about landmarks.
Performance issues directly impact user engagement and conversion rates.
| Failing Elements |
|---|
html.plugin-pages html.plugin-pages |
These items highlight common accessibility best practices.
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
Performance issues directly impact user engagement and conversion rates.
| Source | Description |
|---|---|
jestjs.io/assets/js/main.17432a57.js line 1, col 18234 | Docusaurus React Root onRecoverableError: Error: Minified React error #418; visit https://reactjs.org/docs/error-decoder.html?invariant=418 for the full message or use the non-minified dev environment for full errors and additional helpful warnings.
at ua (https://jestjs.io/assets/js/main.17432a57.js:2:168788)
at Sl (https://jestjs.io/assets/js/main.17432a57.js:2:241454)
at vc (https://jestjs.io/assets/js/main.17432a57.js:2:229012)
at yc (https://jestjs.io/assets/js/main.17432a57.js:2:228984)
at oc (https://jestjs.io/assets/js/main.17432a57.js:2:224065)
at k (https://jestjs.io/assets/js/main.17432a57.js:2:400372)
at MessagePort.P (https://jestjs.io/assets/js/main.17432a57.js:2:400904) [object Object] |
jestjs.io/assets/js/main.17432a57.js line 1, col 18234 | Docusaurus React Root onRecoverableError: Error: Minified React error #418; visit https://reactjs.org/docs/error-decoder.html?invariant=418 for the full message or use the non-minified dev environment for full errors and additional helpful warnings.
at ua (https://jestjs.io/assets/js/main.17432a57.js:2:168788)
at Sl (https://jestjs.io/assets/js/main.17432a57.js:2:241454)
at vc (https://jestjs.io/assets/js/main.17432a57.js:2:229012)
at yc (https://jestjs.io/assets/js/main.17432a57.js:2:228984)
at oc (https://jestjs.io/assets/js/main.17432a57.js:2:224065)
at k (https://jestjs.io/assets/js/main.17432a57.js:2:400372)
at MessagePort.P (https://jestjs.io/assets/js/main.17432a57.js:2:400904) [object Object] |
jestjs.io/assets/js/main.17432a57.js line 1, col 18234 | Docusaurus React Root onRecoverableError: Error: Minified React error #418; visit https://reactjs.org/docs/error-decoder.html?invariant=418 for the full message or use the non-minified dev environment for full errors and additional helpful warnings.
at ua (https://jestjs.io/assets/js/main.17432a57.js:2:168788)
at Sl (https://jestjs.io/assets/js/main.17432a57.js:2:241454)
at vc (https://jestjs.io/assets/js/main.17432a57.js:2:229012)
at yc (https://jestjs.io/assets/js/main.17432a57.js:2:228984)
at oc (https://jestjs.io/assets/js/main.17432a57.js:2:224065)
at k (https://jestjs.io/assets/js/main.17432a57.js:2:400372)
at MessagePort.P (https://jestjs.io/assets/js/main.17432a57.js:2:400904) [object Object] |
jestjs.io/assets/js/main.17432a57.js line 1, col 18234 | Docusaurus React Root onRecoverableError: Error: Minified React error #418; visit https://reactjs.org/docs/error-decoder.html?invariant=418 for the full message or use the non-minified dev environment for full errors and additional helpful warnings.
at ua (https://jestjs.io/assets/js/main.17432a57.js:2:168788)
at Sl (https://jestjs.io/assets/js/main.17432a57.js:2:241454)
at vc (https://jestjs.io/assets/js/main.17432a57.js:2:229012)
at yc (https://jestjs.io/assets/js/main.17432a57.js:2:228984)
at oc (https://jestjs.io/assets/js/main.17432a57.js:2:224065)
at k (https://jestjs.io/assets/js/main.17432a57.js:2:400372)
at MessagePort.P (https://jestjs.io/assets/js/main.17432a57.js:2:400904) [object Object] |
jestjs.io/assets/js/main.17432a57.js line 1, col 18234 | Docusaurus React Root onRecoverableError: Error: Minified React error #418; visit https://reactjs.org/docs/error-decoder.html?invariant=418 for the full message or use the non-minified dev environment for full errors and additional helpful warnings.
at ua (https://jestjs.io/assets/js/main.17432a57.js:2:168788)
at Sl (https://jestjs.io/assets/js/main.17432a57.js:2:241454)
at vc (https://jestjs.io/assets/js/main.17432a57.js:2:229012)
at yc (https://jestjs.io/assets/js/main.17432a57.js:2:228984)
at oc (https://jestjs.io/assets/js/main.17432a57.js:2:224065)
at k (https://jestjs.io/assets/js/main.17432a57.js:2:400372)
at MessagePort.P (https://jestjs.io/assets/js/main.17432a57.js:2:400904) [object Object] |
jestjs.io/assets/js/main.17432a57.js line 1, col 18234 | Docusaurus React Root onRecoverableError: Error: Minified React error #418; visit https://reactjs.org/docs/error-decoder.html?invariant=418 for the full message or use the non-minified dev environment for full errors and additional helpful warnings.
at ua (https://jestjs.io/assets/js/main.17432a57.js:2:168788)
at Sl (https://jestjs.io/assets/js/main.17432a57.js:2:241454)
at vc (https://jestjs.io/assets/js/main.17432a57.js:2:229012)
at yc (https://jestjs.io/assets/js/main.17432a57.js:2:228984)
at oc (https://jestjs.io/assets/js/main.17432a57.js:2:224065)
at k (https://jestjs.io/assets/js/main.17432a57.js:2:400372)
at MessagePort.P (https://jestjs.io/assets/js/main.17432a57.js:2:400904) [object Object] |
jestjs.io/assets/js/main.17432a57.js line 1, col 18234 | Docusaurus React Root onRecoverableError: Error: Minified React error #418; visit https://reactjs.org/docs/error-decoder.html?invariant=418 for the full message or use the non-minified dev environment for full errors and additional helpful warnings.
at ua (https://jestjs.io/assets/js/main.17432a57.js:2:168788)
at Sl (https://jestjs.io/assets/js/main.17432a57.js:2:241454)
at vc (https://jestjs.io/assets/js/main.17432a57.js:2:229012)
at yc (https://jestjs.io/assets/js/main.17432a57.js:2:228984)
at oc (https://jestjs.io/assets/js/main.17432a57.js:2:224065)
at k (https://jestjs.io/assets/js/main.17432a57.js:2:400372)
at MessagePort.P (https://jestjs.io/assets/js/main.17432a57.js:2:400904) [object Object] |
jestjs.io/assets/js/main.17432a57.js line 1, col 18234 | Docusaurus React Root onRecoverableError: Error: Minified React error #418; visit https://reactjs.org/docs/error-decoder.html?invariant=418 for the full message or use the non-minified dev environment for full errors and additional helpful warnings.
at ua (https://jestjs.io/assets/js/main.17432a57.js:2:168788)
at Sl (https://jestjs.io/assets/js/main.17432a57.js:2:241454)
at vc (https://jestjs.io/assets/js/main.17432a57.js:2:229012)
at yc (https://jestjs.io/assets/js/main.17432a57.js:2:228984)
at oc (https://jestjs.io/assets/js/main.17432a57.js:2:224065)
at k (https://jestjs.io/assets/js/main.17432a57.js:2:400372)
at MessagePort.P (https://jestjs.io/assets/js/main.17432a57.js:2:400904) [object Object] |
jestjs.io/assets/js/main.17432a57.js line 1, col 18234 | Docusaurus React Root onRecoverableError: Error: Minified React error #418; visit https://reactjs.org/docs/error-decoder.html?invariant=418 for the full message or use the non-minified dev environment for full errors and additional helpful warnings.
at ua (https://jestjs.io/assets/js/main.17432a57.js:2:168788)
at Sl (https://jestjs.io/assets/js/main.17432a57.js:2:241454)
at vc (https://jestjs.io/assets/js/main.17432a57.js:2:229012)
at yc (https://jestjs.io/assets/js/main.17432a57.js:2:228984)
at oc (https://jestjs.io/assets/js/main.17432a57.js:2:224065)
at k (https://jestjs.io/assets/js/main.17432a57.js:2:400372)
at MessagePort.P (https://jestjs.io/assets/js/main.17432a57.js:2:400904) [object Object] |
jestjs.io/assets/js/main.17432a57.js line 1, col 18234 | Docusaurus React Root onRecoverableError: Error: Minified React error #418; visit https://reactjs.org/docs/error-decoder.html?invariant=418 for the full message or use the non-minified dev environment for full errors and additional helpful warnings.
at ua (https://jestjs.io/assets/js/main.17432a57.js:2:168788)
at Sl (https://jestjs.io/assets/js/main.17432a57.js:2:241454)
at vc (https://jestjs.io/assets/js/main.17432a57.js:2:229012)
at yc (https://jestjs.io/assets/js/main.17432a57.js:2:228984)
at oc (https://jestjs.io/assets/js/main.17432a57.js:2:224065)
at k (https://jestjs.io/assets/js/main.17432a57.js:2:400372)
at MessagePort.P (https://jestjs.io/assets/js/main.17432a57.js:2:400904) [object Object] |
jestjs.io/assets/js/main.17432a57.js line 1, col 18234 | Docusaurus React Root onRecoverableError: Error: Minified React error #423; visit https://reactjs.org/docs/error-decoder.html?invariant=423 for the full message or use the non-minified dev environment for full errors and additional helpful warnings.
at Sl (https://jestjs.io/assets/js/main.17432a57.js:2:241140)
at vc (https://jestjs.io/assets/js/main.17432a57.js:2:229012)
at bc (https://jestjs.io/assets/js/main.17432a57.js:2:228940)
at gc (https://jestjs.io/assets/js/main.17432a57.js:2:228803)
at ac (https://jestjs.io/assets/js/main.17432a57.js:2:225638)
at oc (https://jestjs.io/assets/js/main.17432a57.js:2:224193)
at k (https://jestjs.io/assets/js/main.17432a57.js:2:400372)
at MessagePort.P (https://jestjs.io/assets/js/main.17432a57.js:2:400904) [object Object] |
SEO
These checks ensure that your page is following basic search engine optimization advice. There are many additional factors Lighthouse does not score here that may affect your search ranking, including performance on Core Web Vitals. Learn more about Google Search Essentials.
Content Best Practices
Meta descriptions may be included in search results to concisely summarize page content. Learn more about the meta description.
Performance issues directly impact user engagement and conversion rates.
Format your HTML in a way that enables crawlers to better understand your app’s content.
Crawling and Indexing
Search engines may use `href` attributes on links to crawl websites. Ensure that the `href` attribute of anchor elements links to an appropriate destination, so more pages of the site can be discovered. Learn how to make links crawlable
Performance issues directly impact user engagement and conversion rates.
| Uncrawlable Link |
|---|
toBe div.blockElement > div.blockContent > p.buttons-wrapper > a.button |
toBeCloseTo div.blockElement > div.blockContent > p.buttons-wrapper > a.button |
toEqual div.blockElement > div.blockContent > p.buttons-wrapper > a.button |
toStrictEqual div.blockElement > div.blockContent > p.buttons-wrapper > a.button |
toHaveProperty div.blockElement > div.blockContent > p.buttons-wrapper > a.button |
toMatchSnapshot div.blockElement > div.blockContent > p.buttons-wrapper > a.button |
toThrowError div.blockElement > div.blockContent > p.buttons-wrapper > a.button |
To appear in search results, crawlers need access to your app.