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 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.
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 |
|---|---|---|
| browser.sentry-cdn.com/7.116.0/bundle.tracing.min.js | 110.2 KiB | 1.4 s |
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.
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 | |
|---|---|---|---|
40% off team training
*up to 125 licenses div.css-1rqnzpz > div.css-gstc03 > div.css-18rhart > img | /api/utilities/v1/imageproxy/https://images.ctfassets.net... | 94.1 KiB | 70.3 KiB |
€205/year div.css-1rqnzpz > div.css-gstc03 > div.css-18rhart > img | /api/utilities/v1/imageproxy/https://images.ctfassets.net... | 67.6 KiB | 50.5 KiB |
div.cds-ProductCard-listCard > div.cds-ProductCard-listContentContainer > div.cds-ProductCard-listPreviewImage > img div.cds-ProductCard-listCard > div.cds-ProductCard-listContentContainer > div.cds-ProductCard-listPreviewImage > img | /api/utilities/v1/imageproxy/https://coursera-course-phot... | 17.0 KiB | 15.3 KiB |
div.cds-ProductCard-gridCard > div.cds-ProductCard-gridPreviewContainer > div.cds-CommonCard-previewImage > img div.cds-ProductCard-gridCard > div.cds-ProductCard-gridPreviewContainer > div.cds-CommonCard-previewImage > img | /api/utilities/v1/imageproxy/https://d15cw65ipctsrr.cloud... | 25.1 KiB | 13.3 KiB |
div.cds-ProductCard-gridCard > div.cds-ProductCard-gridPreviewContainer > div.cds-CommonCard-previewImage > img div.cds-ProductCard-gridCard > div.cds-ProductCard-gridPreviewContainer > div.cds-CommonCard-previewImage > img | /api/utilities/v1/imageproxy/https://d15cw65ipctsrr.cloud... | 24.5 KiB | 12.7 KiB |
div.css-18htstt > div.css-1ht76x9 > picture > img div.css-18htstt > div.css-1ht76x9 > picture > img | /api/utilities/v1/imageproxy/https://images.ctfassets.net... | 17.2 KiB | 12.4 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 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 |
|---|---|---|
| /webapps/r2-builds/br/front-page/en.app.065b0df2eb410c5e1... | 426.0 KiB | 152.5 KiB |
| /webapps/r2-builds/br/front-page/13.0842390ff078322547ec.js | 230.7 KiB | 113.0 KiB |
| /webapps/r2-builds/br/front-page/en.14.f1452cee01d415df84... | 285.1 KiB | 102.2 KiB |
| www.googletagmanager.com/gtm.js?id=GTM-5JKLVK&l=dataLayer | 226.3 KiB | 71.2 KiB |
| accounts.google.com/gsi/client | 92.7 KiB | 70.1 KiB |
| www.googletagmanager.com/gtag/destination?id=AW-927621030&cx=c>m=4e6460 | 138.7 KiB | 68.0 KiB |
| www.googletagmanager.com/gtag/js?id=AW-11173242093&cx=c>m=4e6460 | 138.5 KiB | 62.4 KiB |
| browser.sentry-cdn.com/7.116.0/bundle.tracing.min.js | 109.9 KiB | 59.7 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 |
|---|---|---|---|
| /webapps/r2-builds/br/front-page/en.app.065b0df2eb410c5e1... | 3.6 s | 3.2 s | 160 ms |
| www.coursera.org/ | 3.4 s | 55 ms | 28 ms |
| Unattributable | 905 ms | 27 ms | 0.0 ms |
| /webapps/r2-builds/br/front-page/en.14.f1452cee01d415df84... | 659 ms | 485 ms | 137 ms |
| www.googletagmanager.com/gtm.js?id=GTM-5JKLVK&l=dataLayer | 630 ms | 511 ms | 103 ms |
| browser.sentry-cdn.com/7.116.0/bundle.tracing.min.js | 340 ms | 126 ms | 8.4 ms |
| www.googletagmanager.com/gtag/destination?id=AW-927621030&cx=c>m=4e6460 | 279 ms | 237 ms | 40 ms |
| www.googletagmanager.com/gtag/js?id=AW-11173242093&cx=c>m=4e6460 | 132 ms | 99 ms | 32 ms |
| /webapps/r2-builds/br/front-page/13.0842390ff078322547ec.js | 117 ms | 2.0 ms | 114 ms |
| accounts.google.com/gsi/client | 64 ms | 44 ms | 19 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 | 4.8 s |
| Other | 2.4 s |
| Rendering | 1.2 s |
| Style & Layout | 790 ms |
| Script Parsing & Compilation | 718 ms |
| Garbage Collection | 250 ms |
| Parse HTML & CSS | 100 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
Performance issues directly impact user engagement and conversion rates.
| Failure reason | Failure type |
|---|---|
| Pages with cache-control:no-store header cannot enter back/forward cache. | Actionable |
| Pages whose main resource has cache-control:no-store cannot enter back/forward cache. | Not actionable |
| Back/forward cache is disabled because some JavaScript network request received resource with Cache-Control: no-store header. | Not actionable |
Minifying CSS files can reduce network payload sizes. Learn how to minify CSS.
Performance issues directly impact user engagement and conversion rates.
| URL | Transfer Size | Est Savings |
|---|---|---|
| .css-y40tq5 { position: relative; top: 0px; width: 100%; … } … | 42.6 KiB | 3.2 KiB |
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 |
|---|---|---|
| .css-y40tq5 { position: relative; top: 0px; width: 100%; … } … | 42.6 KiB | 40.6 KiB |
| :root{-webkit-print-color-scheme:light;color-scheme:light;--cds-color-darken-975:rgba(15, 17, 20, 0… | 30.9 KiB | 19.2 KiB |
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 | |
|---|---|
€205/year div.css-1rqnzpz > div.css-gstc03 > div.css-18rhart > img | /api/utilities/v1/imageproxy/https://images.ctfassets.net... |
40% off team training
*up to 125 licenses div.css-1rqnzpz > div.css-gstc03 > div.css-18rhart > img | /api/utilities/v1/imageproxy/https://images.ctfassets.net... |
div.css-18htstt > div.css-1ht76x9 > picture > img div.css-18htstt > div.css-1ht76x9 > picture > img | /api/utilities/v1/imageproxy/https://images.ctfassets.net... |
€205/year div.css-9juyzi > div.css-tt9t7i > picture > img | /api/utilities/v1/imageproxy/https://images.ctfassets.net... |
40% off team training
*up to 125 licenses div.css-15xrox9 > div.css-tt9t7i > picture > img | /api/utilities/v1/imageproxy/https://images.ctfassets.net... |
div.css-150mpqx > div.css-tt9t7i > picture > img div.css-150mpqx > div.css-tt9t7i > picture > img | /api/utilities/v1/imageproxy/https://images.ctfassets.net... |
div > div.css-1xgnkn7 > div > img div > div.css-1xgnkn7 > div > img | /api/utilities/v1/imageproxy/https://images.ctfassets.net... |
div > div.css-19incsy > div.css-phfvho > img.css-1080lsv div > div.css-19incsy > div.css-phfvho > img.css-1080lsv | /api/utilities/v1/imageproxy/https://images.ctfassets.net... |
div > div.css-19incsy > div.css-phfvho > img.css-1080lsv div > div.css-19incsy > div.css-phfvho > img.css-1080lsv | /api/utilities/v1/imageproxy/https://images.ctfassets.net... |
div > div.css-19incsy > div.css-phfvho > img.css-1080lsv div > div.css-19incsy > div.css-phfvho > img.css-1080lsv | /api/utilities/v1/imageproxy/https://images.ctfassets.net... |
div > div.css-19incsy > div.css-phfvho > img.css-1080lsv div > div.css-19incsy > div.css-phfvho > img.css-1080lsv | /api/utilities/v1/imageproxy/https://images.ctfassets.net... |
div.css-15xrox9 > div.css-l88zs4 > div > img div.css-15xrox9 > div.css-l88zs4 > div > img | /api/utilities/v1/imageproxy/https://images.ctfassets.net... |
Use 16 px div.css-9juyzi > div.css-l88zs4 > div > img | /api/utilities/v1/imageproxy/https://images.ctfassets.net... |
Use 16 px div > div.css-1xgnkn7 > div > img | /api/utilities/v1/imageproxy/https://images.ctfassets.net... |
div > div.css-akqzvp > a.cds-119 > img.css-11x1h9e div > div.css-akqzvp > a.cds-119 > img.css-11x1h9e | /api/utilities/v1/imageproxy/https://images.ctfassets.net... |
div > div.css-akqzvp > a.cds-119 > img.css-11x1h9e div > div.css-akqzvp > a.cds-119 > img.css-11x1h9e | /api/utilities/v1/imageproxy/https://images.ctfassets.net... |
div > div.css-akqzvp > a.cds-119 > img.css-11x1h9e div > div.css-akqzvp > a.cds-119 > img.css-11x1h9e | /api/utilities/v1/imageproxy/https://images.ctfassets.net... |
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.
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.
Performance issues directly impact user engagement and conversion rates.
| Failing Elements |
|---|
div.cds-9 > div.cds-9 > div.css-1cn6k0e > a.cds-149 div.cds-9 > div.cds-9 > div.css-1cn6k0e > a.cds-149 |
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
User Experience
Image display dimensions should match natural aspect ratio. Learn more about image aspect ratio.
Performance issues directly impact user engagement and conversion rates.
| URL | Aspect Ratio (Displayed) | Aspect Ratio (Actual) | |
|---|---|---|---|
Logo of Certified B Corporation div.cds-9 > div.b-corp-logo > div.css-1oxwx8r > img.css-3gbnhs | /api/utilities/v1/imageproxy/https://d3njjcbhbojbot.cloud... | 111 x 88 (1.26) | 223 x 240 (0.93) |
General
Deprecated APIs will eventually be removed from the browser. Learn more about deprecated APIs.
Performance issues directly impact user engagement and conversion rates.
| Deprecation / Warning | Source |
|---|---|
| Unload event listeners are deprecated and will be removed. | browser.sentry-cdn.com/7.116.0/bundle.tracing.min.js line 1, col 105184 |
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 |
|---|---|
browser.sentry-cdn.com/7.116.0/bundle.tracing.min.js line 1, col 7754 | [GSI_LOGGER]: FedCM get() rejects with NetworkError: Error retrieving a token. |
browser.sentry-cdn.com/7.116.0/bundle.tracing.min.js line 1, col 7754 | {"stack":"Error: Minified React error #419; visit https://reactjs.org/docs/error-decoder.html?invariant=419 for the full message or use the non-minified dev environment for full errors and additional helpful warnings.\n at https://d3njjcbhbojbot.cloudfront.net/webapps/r2-builds/br/front-page/en.app.065b0df2eb410c5e1c70.js:2:1671518\n at oj (https://d3njjcbhbojbot.cloudfront.net/webapps/r2-builds/br/front-page/en.app.065b0df2eb410c5e1c70.js:2:1672357)\n at Yo (https://d3njjcbhbojbot.cloudfront.net/webapps/r2-builds/br/front-page/en.app.065b0df2eb410c5e1c70.js:2:1714760)\n at Uk (https://d3njjcbhbojbot.cloudfront.net/webapps/r2-builds/br/front-page/en.app.065b0df2eb410c5e1c70.js:2:1701783)\n at Tk (https://d3njjcbhbojbot.cloudfront.net/webapps/r2-builds/br/front-page/en.app.065b0df2eb410c5e1c70.js:2:1701711)\n at Ik (https://d3njjcbhbojbot.cloudfront.net/webapps/r2-builds/br/front-page/en.app.065b0df2eb410c5e1c70.js:2:1701574)\n at Ek (https://d3njjcbhbojbot.cloudfront.net/webapps/r2-builds/br/front-page/en.app.065b0df2eb410c5e1c70.js:2:1698633)\n at jg (https://d3njjcbhbojbot.cloudfront.net/webapps/r2-builds/br/front-page/en.app.065b0df2eb410c5e1c70.js:2:1638182)\n at https://d3njjcbhbojbot.cloudfront.net/webapps/r2-builds/br/front-page/en.app.065b0df2eb410c5e1c70.js:2:1705222\n at Pk (https://d3njjcbhbojbot.cloudfront.net/webapps/r2-builds/br/front-page/en.app.065b0df2eb410c5e1c70.js:2:1705227)\n at Gk (https://d3njjcbhbojbot.cloudfront.net/webapps/r2-builds/br/front-page/en.app.065b0df2eb410c5e1c70.js:2:1697571)\n at J (https://d3njjcbhbojbot.cloudfront.net/webapps/r2-builds/br/front-page/en.app.065b0df2eb410c5e1c70.js:2:579322)\n at R (https://d3njjcbhbojbot.cloudfront.net/webapps/r2-builds/br/front-page/en.app.065b0df2eb410c5e1c70.js:2:579903)\n at Ge.tt.<computed> (https://d3njjcbhbojbot.cloudfront.net/webapps/r2-builds/br/front-page/en.app.065b0df2eb410c5e1c70.js:2:599386)\n at run (https://d3njjcbhbojbot.cloudfront.net/webapps/r2-builds/br/front-page/en.app.065b0df2eb410c5e1c70.js:2:599125)\n at MessagePort.listener (https://d3njjcbhbojbot.cloudfront.net/webapps/r2-builds/br/front-page/en.app.065b0df2eb410c5e1c70.js:2:599198)","message":"Minified React error #419; visit https://reactjs.org/docs/error-decoder.html?invariant=419 for the full message or use the non-minified dev environment for full errors and additional helpful warnings."} |
/webapps/r2-builds/br/front-page/en.app.065b0df2eb410c5e1... line 1, col 1671517 | Error: Minified React error #419; visit https://reactjs.org/docs/error-decoder.html?invariant=419 for the full message or use the non-minified dev environment for full errors and additional helpful warnings.
at https://d3njjcbhbojbot.cloudfront.net/webapps/r2-builds/br/front-page/en.app.065b0df2eb410c5e1c70.js:2:1671518
at oj (https://d3njjcbhbojbot.cloudfront.net/webapps/r2-builds/br/front-page/en.app.065b0df2eb410c5e1c70.js:2:1672357)
at Yo (https://d3njjcbhbojbot.cloudfront.net/webapps/r2-builds/br/front-page/en.app.065b0df2eb410c5e1c70.js:2:1714760)
at Uk (https://d3njjcbhbojbot.cloudfront.net/webapps/r2-builds/br/front-page/en.app.065b0df2eb410c5e1c70.js:2:1701783)
at Tk (https://d3njjcbhbojbot.cloudfront.net/webapps/r2-builds/br/front-page/en.app.065b0df2eb410c5e1c70.js:2:1701711)
at Ik (https://d3njjcbhbojbot.cloudfront.net/webapps/r2-builds/br/front-page/en.app.065b0df2eb410c5e1c70.js:2:1701574)
at Ek (https://d3njjcbhbojbot.cloudfront.net/webapps/r2-builds/br/front-page/en.app.065b0df2eb410c5e1c70.js:2:1698633)
at jg (https://d3njjcbhbojbot.cloudfront.net/webapps/r2-builds/br/front-page/en.app.065b0df2eb410c5e1c70.js:2:1638182)
at https://d3njjcbhbojbot.cloudfront.net/webapps/r2-builds/br/front-page/en.app.065b0df2eb410c5e1c70.js:2:1705222
at Pk (https://d3njjcbhbojbot.cloudfront.net/webapps/r2-builds/br/front-page/en.app.065b0df2eb410c5e1c70.js:2:1705227)
at Gk (https://d3njjcbhbojbot.cloudfront.net/webapps/r2-builds/br/front-page/en.app.065b0df2eb410c5e1c70.js:2:1697571)
at J (https://d3njjcbhbojbot.cloudfront.net/webapps/r2-builds/br/front-page/en.app.065b0df2eb410c5e1c70.js:2:579322)
at R (https://d3njjcbhbojbot.cloudfront.net/webapps/r2-builds/br/front-page/en.app.065b0df2eb410c5e1c70.js:2:579903)
at Ge.tt.<computed> (https://d3njjcbhbojbot.cloudfront.net/webapps/r2-builds/br/front-page/en.app.065b0df2eb410c5e1c70.js:2:599386)
at run (https://d3njjcbhbojbot.cloudfront.net/webapps/r2-builds/br/front-page/en.app.065b0df2eb410c5e1c70.js:2:599125)
at MessagePort.listener (https://d3njjcbhbojbot.cloudfront.net/webapps/r2-builds/br/front-page/en.app.065b0df2eb410c5e1c70.js:2:599198) |
Not signed in with the identity provider. |
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.