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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.

85

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
/stable/_static/scripts/fontawesome.js?digest=8878045cc6d...600.0 s540.8 KiB
scikit-learn.org/stable/_static/vendor/fontawesome/webfonts/fa-solid-900.woff2600.0 s153.0 KiB
/stable/_images/sphx_glr_plot_classifier_comparison_001_c...600.0 s152.9 KiB
scikit-learn.org/stable/_static/vendor/fontawesome/webfonts/fa-brands-400.woff2600.0 s115.3 KiB
scikit-learn.org/stable/_images/sphx_glr_plot_hgbt_regression_002.png600.0 s99.4 KiB
/stable/_images/sphx_glr_plot_discretization_strategies_t...600.0 s88.9 KiB
scikit-learn.org/stable/_images/sphx_glr_plot_kmeans_digits_thumb.png600.0 s65.2 KiB
/stable/_static/styles/pydata-sphinx-theme.css?digest=887...600.0 s65.1 KiB
scikit-learn.org/stable/_images/sphx_glr_plot_pca_iris_thumb.png600.0 s45.3 KiB
scikit-learn.org/stable/_images/aweber.png600.0 s40.7 KiB
scikit-learn.org/stable/_static/scripts/bootstrap.js?digest=8878045cc6db502f8baf600.0 s23.6 KiB
scikit-learn.org/stable/_images/inria.png600.0 s23.6 KiB
scikit-learn.org/stable/_static/probabl.png600.0 s20.0 KiB
scikit-learn.org/stable/_images/sphx_glr_plot_multi_metric_evaluation_thumb.png600.0 s17.1 KiB
scikit-learn.org/stable/_static/czi-small.png600.0 s16.0 KiB
scikit-learn.org/stable/_images/spotify.png600.0 s12.2 KiB
scikit-learn.org/stable/_images/telecomparistech.jpg600.0 s11.4 KiB
scikit-learn.org/stable/_static/quansight-labs-small.png600.0 s8.4 KiB
scikit-learn.org/stable/_static/microsoft-small.png600.0 s8.1 KiB
scikit-learn.org/stable/_static/nvidia-small.png600.0 s8.1 KiB
scikit-learn.org/stable/_static/sphinx-design.min.css?v=95c83b7e600.0 s7.2 KiB
scikit-learn.org/stable/_static/wellcome-trust-small.png600.0 s7.1 KiB
scikit-learn.org/stable/_static/inria-small.png600.0 s7.1 KiB
scikit-learn.org/stable/_images/yhat.png600.0 s6.4 KiB
scikit-learn.org/stable/_static/chanel-small.png600.0 s4.6 KiB
/stable/_static/scripts/pydata-sphinx-theme.js?digest=887...600.0 s4.4 KiB
scikit-learn.org/stable/_static/scikit-learn-logo-without-subtitle.svg600.0 s3.7 KiB
scikit-learn.org/stable/_static/basic.css600.0 s3.6 KiB
scikit-learn.org/stable/_images/change-logo.png600.0 s3.4 KiB
scikit-learn.org/stable/_static/copybutton.js?v=97f0b27d600.0 s3.3 KiB
scikit-learn.org/stable/_static/jupyterlite_sphinx.js?v=96e329c5600.0 s3.3 KiB
scikit-learn.org/stable/_static/clipboard.min.js?v=a7894cd8600.0 s3.3 KiB
scikit-learn.org/stable/_static/sg_gallery.css?v=d2d258e8600.0 s2.9 KiB
scikit-learn.org/stable/_static/sphinx_highlight.js?v=dc90522c600.0 s2.2 KiB
scikit-learn.org/stable/_static/pygments.css?v=8f2a1f02600.0 s2.0 KiB
scikit-learn.org/stable/_static/styles/custom.css?v=eec3fc85600.0 s1.9 KiB
scikit-learn.org/stable/_static/doctools.js?v=9bcbadda600.0 s1.8 KiB
scikit-learn.org/stable/_static/design-tabs.js?v=f930bc37600.0 s1.3 KiB
scikit-learn.org/stable/_static/styles/index.css?v=e49e61c4600.0 s1.3 KiB
scikit-learn.org/stable/_static/sg_gallery-rendered-html.css?v=1277b6f3600.0 s1.2 KiB
scikit-learn.org/stable/_static/scripts/dropdown.js?v=d6825577600.0 s1.2 KiB
scikit-learn.org/stable/_static/copybutton.css?v=76b2166b600.0 s987 B
scikit-learn.org/stable/_static/scripts/version-switcher.js?v=a6dd8357600.0 s823 B
scikit-learn.org/stable/_static/jupyterlite_sphinx.css?v=8ee2c72c600.0 s815 B
scikit-learn.org/stable/_static/styles/colors.css?v=cc94ab7d600.0 s749 B
scikit-learn.org/stable/_static/sg_gallery-dataframe.css?v=2082cf3c600.0 s748 B
scikit-learn.org/stable/_static/scripts/sg_plotly_resize.js?v=2167d4db600.0 s569 B
scikit-learn.org/stable/_static/scripts/theme-observer.js?v=bf5fb916600.0 s568 B
scikit-learn.org/stable/_static/plot_directive.css600.0 s465 B
scikit-learn.org/stable/_static/documentation_options.js?v=b51e6972600.0 s423 B
scikit-learn.org/stable/_static/sg_gallery-binder.css?v=f4aeca0c600.0 s408 B
scikit-learn.org/stable/_static/styles/theme.css?digest=8878045cc6db502f8baf600.0 s332 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.

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
Classifier comparison div.card > div.sk-card-img-container > a > img
/stable/_images/sphx_glr_plot_classifier_comparison_001_c...152.6 KiB134.0 KiB
Decision Tree Regression with HGBT div.card > div.sk-card-img-container > a > img
scikit-learn.org/stable/_images/sphx_glr_plot_hgbt_regression_002.png99.1 KiB80.3 KiB
Demonstrating the different strategies of KBinsDiscretizer div.card > div.sk-card-img-container > a > img
/stable/_images/sphx_glr_plot_discretization_strategies_t...88.7 KiB75.3 KiB
A demo of K-Means clustering on the handwritten digits data div.card > div.sk-card-img-container > a > img
scikit-learn.org/stable/_images/sphx_glr_plot_kmeans_digits_thumb.png65.0 KiB51.6 KiB
PCA example with Iris Data-set div.card > div.sk-card-img-container > a > img
scikit-learn.org/stable/_images/sphx_glr_plot_pca_iris_thumb.png45.1 KiB31.7 KiB
inria div#skWhoUsesCarousel > div.carousel-inner > div.carousel-item > img.d-block
scikit-learn.org/stable/_images/inria.png23.3 KiB20.7 KiB
a.sk-footer-funding-link > div.text-center > div.sk-footer-funding-logos > img a.sk-footer-funding-link > div.text-center > div.sk-footer-funding-logos > img
scikit-learn.org/stable/_static/probabl.png19.7 KiB19.7 KiB
a.sk-footer-funding-link > div.text-center > div.sk-footer-funding-logos > img a.sk-footer-funding-link > div.text-center > div.sk-footer-funding-logos > img
scikit-learn.org/stable/_static/czi-small.png15.7 KiB15.6 KiB
a.sk-footer-funding-link > div.text-center > div.sk-footer-funding-logos > img a.sk-footer-funding-link > div.text-center > div.sk-footer-funding-logos > img
scikit-learn.org/stable/_static/quansight-labs-small.png8.2 KiB7.9 KiB
a.sk-footer-funding-link > div.text-center > div.sk-footer-funding-logos > img a.sk-footer-funding-link > div.text-center > div.sk-footer-funding-logos > img
scikit-learn.org/stable/_static/microsoft-small.png7.9 KiB7.7 KiB
a.sk-footer-funding-link > div.text-center > div.sk-footer-funding-logos > img a.sk-footer-funding-link > div.text-center > div.sk-footer-funding-logos > img
scikit-learn.org/stable/_static/nvidia-small.png7.9 KiB7.7 KiB
a.sk-footer-funding-link > div.text-center > div.sk-footer-funding-logos > img a.sk-footer-funding-link > div.text-center > div.sk-footer-funding-logos > img
scikit-learn.org/stable/_static/wellcome-trust-small.png6.9 KiB6.8 KiB
a.sk-footer-funding-link > div.text-center > div.sk-footer-funding-logos > img a.sk-footer-funding-link > div.text-center > div.sk-footer-funding-logos > img
scikit-learn.org/stable/_static/inria-small.png6.9 KiB6.6 KiB
Demonstration of multi-metric evaluation on cross_val_score and GridSearchCV div.card > div.sk-card-img-container > a > img
scikit-learn.org/stable/_images/sphx_glr_plot_multi_metric_evaluation_thumb.png16.9 KiB4.5 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-1-IMG
nodeLabel: Decision Tree Regression with HGBT
path: 1,HTML,1,BODY,7,DIV,0,DIV,2,MAIN,0,DIV,0,DIV,3,DIV,0,DIV,1,DIV,0,A,0,IMG
selector: div.card > div.sk-card-img-container > a > img
snippet: <img src="_images/sphx_glr_plot_hgbt_regression_002.png" alt="Decision Tree Regression with HGBT">

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
value: No additional origins are good candidates for preconnecting

Requests are blocking the page's initial render, which may delay LCP. Deferring or inlining can move these network requests out of the critical path.

Why this matters

Performance issues directly impact user engagement and conversion rates.

URLTransfer SizeDuration
/stable/_static/scripts/fontawesome.js?digest=8878045cc6d...540.8 KiB440 ms
fonts.googleapis.com/css?family=Vibur747 B223 ms
scikit-learn.org/stable/_static/documentation_options.js?v=b51e6972423 B
scikit-learn.org/stable/_static/jupyterlite_sphinx.js?v=96e329c53.3 KiB
scikit-learn.org/stable/_static/design-tabs.js?v=f930bc371.3 KiB
scikit-learn.org/stable/_static/clipboard.min.js?v=a7894cd83.3 KiB
scikit-learn.org/stable/_static/scripts/theme-observer.js?v=bf5fb916568 B
scikit-learn.org/stable/_static/scripts/sg_plotly_resize.js?v=2167d4db569 B
scikit-learn.org/stable/_static/copybutton.js?v=97f0b27d3.3 KiB
/stable/_static/styles/pydata-sphinx-theme.css?digest=887...65.1 KiB120 ms
scikit-learn.org/stable/_static/scripts/version-switcher.js?v=a6dd8357823 B
scikit-learn.org/stable/_static/sphinx_highlight.js?v=dc90522c2.2 KiB
scikit-learn.org/stable/_static/doctools.js?v=9bcbadda1.8 KiB
scikit-learn.org/stable/_static/basic.css3.6 KiB
scikit-learn.org/stable/_static/scripts/dropdown.js?v=d68255771.2 KiB
scikit-learn.org/stable/_static/styles/custom.css?v=eec3fc851.9 KiB
scikit-learn.org/stable/_static/styles/colors.css?v=cc94ab7d749 B
scikit-learn.org/stable/_static/styles/index.css?v=e49e61c41.3 KiB
scikit-learn.org/stable/_static/sphinx-design.min.css?v=95c83b7e7.2 KiB
scikit-learn.org/stable/_static/sg_gallery-dataframe.css?v=2082cf3c748 B
scikit-learn.org/stable/_static/sg_gallery.css?v=d2d258e82.9 KiB
scikit-learn.org/stable/_static/jupyterlite_sphinx.css?v=8ee2c72c815 B
scikit-learn.org/stable/_static/plot_directive.css465 B
scikit-learn.org/stable/_static/copybutton.css?v=76b2166b987 B
scikit-learn.org/stable/_static/pygments.css?v=8f2a1f022.0 KiB
scikit-learn.org/stable/_static/styles/theme.css?digest=8878045cc6db502f8baf332 B
scikit-learn.org/stable/_static/sg_gallery-binder.css?v=f4aeca0c408 B
scikit-learn.org/stable/_static/sg_gallery-rendered-html.css?v=1277b6f31.2 KiB

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
scikit-learn.org/stable/_static/vendor/fontawesome/webfonts/fa-solid-900.woff215 ms
scikit-learn.org/stable/_static/vendor/fontawesome/webfonts/fa-brands-400.woff215 ms

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: 40 ms 59.6 KiB
URLTransfer SizeEst Savings
/stable/_static/styles/pydata-sphinx-theme.css?digest=887...64.9 KiB59.6 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
scikit-learn homepage div.navbar-header-items__start > div.navbar-item > a.navbar-brand > img.logo__image
scikit-learn.org/stable/_static/scikit-learn-logo-without-subtitle.svg
Decision Tree Regression with HGBT div.card > div.sk-card-img-container > a > img
scikit-learn.org/stable/_images/sphx_glr_plot_hgbt_regression_002.png
a.sk-footer-funding-link > div.text-center > div.sk-footer-funding-logos > img a.sk-footer-funding-link > div.text-center > div.sk-footer-funding-logos > img
scikit-learn.org/stable/_static/probabl.png
Classifier comparison div.card > div.sk-card-img-container > a > img
/stable/_images/sphx_glr_plot_classifier_comparison_001_c...
A demo of K-Means clustering on the handwritten digits data div.card > div.sk-card-img-container > a > img
scikit-learn.org/stable/_images/sphx_glr_plot_kmeans_digits_thumb.png
PCA example with Iris Data-set div.card > div.sk-card-img-container > a > img
scikit-learn.org/stable/_images/sphx_glr_plot_pca_iris_thumb.png
Demonstration of multi-metric evaluation on cross_val_score and GridSearchCV div.card > div.sk-card-img-container > a > img
scikit-learn.org/stable/_images/sphx_glr_plot_multi_metric_evaluation_thumb.png
Demonstrating the different strategies of KBinsDiscretizer div.card > div.sk-card-img-container > a > img
/stable/_images/sphx_glr_plot_discretization_strategies_t...
inria div#skWhoUsesCarousel > div.carousel-inner > div.carousel-item > img.d-block
scikit-learn.org/stable/_images/inria.png
a.sk-footer-funding-link > div.text-center > div.sk-footer-funding-logos > img a.sk-footer-funding-link > div.text-center > div.sk-footer-funding-logos > img
scikit-learn.org/stable/_static/inria-small.png
a.sk-footer-funding-link > div.text-center > div.sk-footer-funding-logos > img a.sk-footer-funding-link > div.text-center > div.sk-footer-funding-logos > img
scikit-learn.org/stable/_static/quansight-labs-small.png
a.sk-footer-funding-link > div.text-center > div.sk-footer-funding-logos > img a.sk-footer-funding-link > div.text-center > div.sk-footer-funding-logos > img
scikit-learn.org/stable/_static/microsoft-small.png
a.sk-footer-funding-link > div.text-center > div.sk-footer-funding-logos > img a.sk-footer-funding-link > div.text-center > div.sk-footer-funding-logos > img
scikit-learn.org/stable/_static/chanel-small.png
a.sk-footer-funding-link > div.text-center > div.sk-footer-funding-logos > img a.sk-footer-funding-link > div.text-center > div.sk-footer-funding-logos > img
scikit-learn.org/stable/_static/nvidia-small.png
a.sk-footer-funding-link > div.text-center > div.sk-footer-funding-logos > img a.sk-footer-funding-link > div.text-center > div.sk-footer-funding-logos > img
scikit-learn.org/stable/_static/czi-small.png
a.sk-footer-funding-link > div.text-center > div.sk-footer-funding-logos > img a.sk-footer-funding-link > div.text-center > div.sk-footer-funding-logos > img
scikit-learn.org/stable/_static/wellcome-trust-small.png
a.sk-footer-funding-link > div.text-center > div.sk-footer-funding-logos > img a.sk-footer-funding-link > div.text-center > div.sk-footer-funding-logos > img
scikit-learn.org/stable/_static/bnp-paribas.png

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: 638 ms
URLTime Spent
scikit-learn.org/216 ms
scikit-learn.github.io/stable190 ms
scikit-learn.github.io/stable122 ms
scikit-learn.org/stable110 ms
scikit-learn.org/stable0.0 ms
scikit-learn.org/stable/0.0 ms
●Time to Interactive 1.8 s
●Max Potential First Input Delay 80 ms
●Layout shift culprits
●Optimize DOM size
●Forced reflow
●LCP breakdown
●Modern HTTP
●Optimize viewport for mobile
●Minify CSS
●Minify JavaScript
●Reduce unused JavaScript
●Avoids enormous network payloads Total size was 1,623 KiB
●JavaScript execution time 0.1 s
●Minimizes main-thread work 0.4 s
●Avoid long main-thread tasks 1 long task found
●Avoid non-composited animations 3 animated elements found
●Page didn't prevent back/forward cache restoration
●Network Requests
●Network Round Trip Times 70 ms
●Server Backend Latencies 20 ms
●Tasks
●Diagnostics
●Metrics
●Screenshot Thumbnails
●Final Screenshot
●Script Treemap Data
●Resources Summary
●Initial server response time was short Root document took 10 ms
●Avoid large layout shifts 2 layout shifts found
○INP breakdown
○User Timing marks and measures
95

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.

Why this matters

Performance issues directly impact user engagement and conversion rates.

Failing Elements
News div.container > div.row > div.col-md-4 > h4.sk-landing-call-header
scikit-learn 1.9 (Changelog) div.col-md-4 > ul.sk-landing-call-list > li > a
Changelog div.col-md-4 > ul.sk-landing-call-list > li > a
Changelog div.col-md-4 > ul.sk-landing-call-list > li > a
Changelog div.col-md-4 > ul.sk-landing-call-list > li > a
Changelog div.col-md-4 > ul.sk-landing-call-list > li > a
Changelog div.col-md-4 > ul.sk-landing-call-list > li > a
Changelog div.col-md-4 > ul.sk-landing-call-list > li > a
What's new (Changelog) div.col-md-4 > ul.sk-landing-call-list > li > a
What's new ul.sk-landing-call-list > li > a > strong
Community div.container > div.row > div.col-md-4 > h4.sk-landing-call-header
people div.col-md-4 > ul.sk-landing-call-list > li > a
contributing div.col-md-4 > ul.sk-landing-call-list > li > a
related projects div.col-md-4 > ul.sk-landing-call-list > li > a
FAQ div.col-md-4 > ul.sk-landing-call-list > li > a
Support div.col-md-4 > ul.sk-landing-call-list > li > a
Discussions div.col-md-4 > ul.sk-landing-call-list > li > a
Stack Overflow div.col-md-4 > ul.sk-landing-call-list > li > a
mailing list div.col-md-4 > ul.sk-landing-call-list > li > a
blog.scikit-learn.org div.col-md-4 > ul.sk-landing-call-list > li > a
logos and branding div.col-md-4 > ul.sk-landing-call-list > li > a
calendar div.col-md-4 > ul.sk-landing-call-list > li > a
scikit-learn central div.col-md-4 > ul.sk-landing-call-list > li > a
linkedin/scikit-learn div.col-md-4 > ul.sk-landing-call-list > li > a
bluesky/scikit-learn.org div.col-md-4 > ul.sk-landing-call-list > li > a
@sklearn div.col-md-4 > ul.sk-landing-call-list > li > a
youtube.com/scikit-learn div.col-md-4 > ul.sk-landing-call-list > li > a
@scikitlearnofficial div.col-md-4 > ul.sk-landing-call-list > li > a
@scikitlearnofficial div.col-md-4 > ul.sk-landing-call-list > li > a
@scikit.learn div.col-md-4 > ul.sk-landing-call-list > li > a
@scikit-learn div.col-md-4 > ul.sk-landing-call-list > li > a
our code of conduct. div.col-md-4 > ul.sk-landing-call-list > li > a
Who uses scikit-learn? div.container > div.row > div.col-md-4 > h4.sk-landing-call-header
More testimonials... div.row > div.col-md-4 > p.sk-more-testimonials > a

These are opportunities to improve the legibility of your content.

Navigation

Properly ordered headings that do not skip levels convey the semantic structure of the page, making it easier to navigate and understand when using assistive technologies. Learn more about heading order.

Why this matters

Performance issues directly impact user engagement and conversion rates.

Failing Elements
Machine Learning in Python div.container > div.row > div.col-md-6 > h4.sk-landing-subheader

These are opportunities to improve keyboard navigation in your application.

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
Color mode div.navbar-header-items > div.navbar-header-items__end > div.navbar-item > button.btn
1.8.0 (stable) div.navbar-header-items__end > div.navbar-item > div.version-switcher__container > button#pst-version-switcher-button-2
○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>`
●`[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
●`[user-scalable="no"]` is not used in the `<meta name="viewport">` element and the `[maximum-scale]` attribute is not less than 5.
●ARIA attributes are used as specified for the element's role
●`[aria-hidden="true"]` elements do not contain focusable descendents
●Elements use only permitted ARIA attributes
●Document has a `<title>` element
●`<html>` element has a `[lang]` attribute
●`<html>` element has a valid value for its `[lang]` attribute
●Links 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
●Touch targets have sufficient size and spacing.
●Skip links are focusable.
●Document has a main landmark.
●Deprecated ARIA roles were not used
●Identical links have the same purpose.
○`[accesskey]` values are unique
○`button`, `link`, and `menuitem` elements have accessible names
○Elements with `role="dialog"` or `role="alertdialog"` have accessible names.
○ARIA input fields have accessible names
○ARIA `meter` elements have accessible names
○ARIA `progressbar` elements have accessible names
○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
○`<frame>` or `<iframe>` elements have a title
○`<html>` element has an `[xml:lang]` attribute with the same base language as the `[lang]` attribute.
○Input buttons have discernible text.
○`<input type="image">` elements have `[alt]` text
○Form elements have associated labels
○The document does not use `<meta http-equiv="refresh">`
○`<object>` elements have alternate text
○Select elements have associated label elements.
○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.
73

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
scikit-learn.github.io/stableAllowed
scikit-learn.org/stableAllowed

Browser Compatibility

Specifying a doctype prevents the browser from switching to quirks-mode. Learn more about the doctype declaration.

Why this matters

Performance issues directly impact user engagement and conversion rates.

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
scikit-learn.org/_static/css/bootstrap-responsive.css
Failed to load resource: the server responded with a status of 404 ()
scikit-learn.org/_static/css/bootstrap.min.css
Failed to load resource: the server responded with a status of 404 ()
scikit-learn.org/_static/gallery.css
Failed to load resource: the server responded with a status of 404 ()
scikit-learn.org/_static/jquery.js
Failed to load resource: the server responded with a status of 404 ()
scikit-learn.org/_static/underscore.js
Failed to load resource: the server responded with a status of 404 ()
scikit-learn.org/_static/nature.css
Failed to load resource: the server responded with a status of 404 ()
scikit-learn.org/_static/js/bootstrap.min.js
Failed to load resource: the server responded with a status of 404 ()
scikit-learn.org/_static/js/copybutton.js
Failed to load resource: the server responded with a status of 404 ()
scikit-learn.org/_static/pygments.css
Failed to load resource: the server responded with a status of 404 ()
scikit-learn.org/_static/doctools.js
Failed to load resource: the server responded with a status of 404 ()
scikit-learn.org/_static/favicon.ico
Failed to load resource: the server responded with a status of 404 ()
scikit-learn.org/stable/_static/bnp-paribas.png
Failed to load resource: the server responded with a status of 404 ()
/stable/_static/scripts/pydata-sphinx-theme.js?digest=887...
Got invalid theme mode: . Resetting to auto.
●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
●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 clickjacking with XFO or CSP
●Mitigate DOM-based XSS with Trusted Types
●Page has valid source maps
○Redirects HTTP traffic to HTTPS
○Detected JavaScript libraries
92

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.

Why this matters

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.

○Structured data is valid
●Page isn’t blocked from indexing
●Document has a `<title>` element
●Page has successful HTTP status code
●Links have descriptive text
●Links are crawlable
●Image elements have `[alt]` attributes
●Document has a valid `hreflang`
●Document has a valid `rel=canonical`
○robots.txt is valid

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