Lighthouse Mobile

· 0 checks — Mobile 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.

Layout shifts occur when elements move absent any user interaction. Investigate the causes of layout shifts, such as elements being added, removed, or their fonts changing as the page loads.

Why this matters

Performance issues directly impact user engagement and conversion rates.

headings: [map[key:node label:Element subItemsHeading:map[key:extra] valueType:node] map[granularity:0.001 key:score label:Layout shift score subItemsHeading:map[key:cause valueType:text] valueType:numeric]]

items: [map[node:map[type:text value:Total] score:0.501191] map[node:map[boundingRect:map[bottom:995 height:313 left:0 right:412 top:682 width:412] lhId:page-1-DIV nodeLabel: The Python Package Index (PyPI) is a repository of software for the Python p… path:1,HTML,1,BODY,7,MAIN,2,DIV selector:body.with-sticky > main#content > div.horizontal-section snippet:<div class="horizontal-section"> type:node] score:0.335942 subItems:map[items:[map[cause:Unsized image element extra:map[boundingRect:map[bottom:195 height:44 left:15 right:65 top:151 width:50] lhId:page-7-IMG nodeLabel:PyPI path:1,HTML,1,BODY,6,HEADER,0,DIV,0,DIV,0,DIV,0,A,0,IMG selector:div.split-layout > div > a.site-header__logo > img snippet:<img alt="PyPI" src="/static/images/logo-small.8998e9d1.svg"> type:node]]] type:subitems]] map[node:map[boundingRect:map[bottom:995 height:783 left:0 right:412 top:211 width:412] lhId:page-5-MAIN nodeLabel:Find, install and publish Python packages with the Python Package Index Search … path:1,HTML,1,BODY,7,MAIN selector:body.with-sticky > main#content snippet:<main id="content"> type:node] score:0.165249 subItems:map[items:[map[cause:Unsized image element extra:map[boundingRect:map[bottom:195 height:44 left:15 right:65 top:151 width:50] lhId:page-7-IMG nodeLabel:PyPI path:1,HTML,1,BODY,6,HEADER,0,DIV,0,DIV,0,DIV,0,A,0,IMG selector:div.split-layout > div > a.site-header__logo > img snippet:<img alt="PyPI" src="/static/images/logo-small.8998e9d1.svg"> type:node]]] type:subitems]]]

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.

URL	Transfer Size	Duration
pypi.org/static/css/fonts.3b5d1a1c.css	17.7 KiB
pypi.org/static/css/fontawesome.379f9724.css	68.7 KiB	450 ms
pypi.org/static/css/warehouse-ltr.0f58843e.css	88.0 KiB	450 ms

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
media.ethicalads.io/media/client/v1.4.0/ethicalads.min.js	3600.0 s	8.7 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.

URL	Est Savings
pypi.org/static/webfonts/fa-solid-900.ce9a3fa7.woff2	10 ms

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

These are the largest layout shifts observed on the page. Each table item represents a single layout shift, and shows the element that shifted the most. Below each item are possible root causes that led to the layout shift. Some of these layout shifts may not be included in the CLS metric value due to windowing. Learn how to improve CLS

Why this matters

Performance issues directly impact user engagement and conversion rates.

Element	Layout shift score
The Python Package Index (PyPI) is a repository of software for the Python p… `body.with-sticky > main#content > div.horizontal-section`	0.336
Find, install and publish Python packages with the Python Package Index Search … `body.with-sticky > main#content`	0.165

Time to Interactive is the amount of time it takes for the page to become fully interactive. Learn more about the Time to Interactive metric.

Why this matters

Performance issues directly impact user engagement and conversion rates.

TTI

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: 600 ms 161.9 KiB

URL	Transfer Size	Est Savings
pypi.org/static/css/warehouse-ltr.0f58843e.css	87.7 KiB	77.0 KiB
pypi.org/static/css/fontawesome.379f9724.css	68.5 KiB	67.3 KiB
pypi.org/static/css/fonts.3b5d1a1c.css	17.5 KiB	17.5 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: 300 ms 66.4 KiB

URL	Transfer Size	Est Savings
pypi.org/static/js/warehouse.e9abdc3b.js	105.0 KiB	66.4 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
PyPI `div.split-layout > div > a.site-header__logo > img`	pypi.org/static/images/logo-small.8998e9d1.svg
body.with-sticky > footer.footer > div.footer__logo > img.-js-white-cube `body.with-sticky > footer.footer > div.footer__logo > img.-js-white-cube`	pypi.org/static/images/white-cube.2351a86c.svg

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

●Max Potential First Input Delay 120 ms

●Document request latency

●Optimize DOM size

●Forced reflow

●Improve image delivery

●LCP breakdown

●Modern HTTP

●Optimize viewport for mobile

●Minify CSS

●Minify JavaScript

●Avoids enormous network payloads Total size was 521 KiB

●JavaScript execution time 0.2 s

●Minimizes main-thread work 0.7 s

●Avoid long main-thread tasks 2 long tasks found

●Page didn't prevent back/forward cache restoration

●Network Requests

●Network Round Trip Times 0 ms

●Server Backend Latencies 60 ms

●Tasks

●Diagnostics

●Metrics

●Screenshot Thumbnails

●Final Screenshot

●Script Treemap Data

●Resources Summary

●Avoid multiple page redirects

●Initial server response time was short Root document took 0 ms

○INP breakdown

○LCP request discovery

○User Timing marks and measures

○Avoid non-composited animations

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.

Best practices

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

Why this matters

Performance issues directly impact user engagement and conversion rates.

Failing Elements
Site map `footer.footer > div.footer__text > p > a`
English `form > ul > li > button.language-switcher__selected`
español `form > ul > li > button`
français `form > ul > li > button`
日本語 `form > ul > li > button`
português (Brasil) `form > ul > li > button`
українська `form > ul > li > button`
Ελληνικά `form > ul > li > button`
Deutsch `form > ul > li > button`
中文 (简体) `form > ul > li > button`
中文 (繁體) `form > ul > li > button`
русский `form > ul > li > button`
עברית `form > ul > li > button`
Esperanto `form > ul > li > button`
한국어 `form > ul > li > button`

These items highlight common accessibility best practices.

○Interactive controls are keyboard focusable

○Interactive elements indicate their purpose and state

○The page has a logical tab order

○Visual order on the page follows DOM order

○User focus is not accidentally trapped in a region

○The user's focus is directed to new content added to the page

○HTML5 landmark elements are used to improve navigation

○Offscreen content is hidden from assistive technology

○Custom controls have associated labels

○Custom controls have ARIA roles

●`[aria-*]` attributes match their roles

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

●`[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

●`[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

●Heading elements appear in a sequentially-descending order

●Skip links are focusable.

●Document has a main landmark.

●Deprecated ARIA roles were not used

●Elements with visible text labels have matching accessible names.

○`[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

○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.

○Identical links have the same purpose.

○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
media.ethicalads.io/media/client/v1.4.0/ethicalads.min.js	`Error: No ad placements found. at w (https://media.ethicalads.io/media/client/v1.4.0/ethicalads.min.js:1:11867) at https://media.ethicalads.io/media/client/v1.4.0/ethicalads.min.js:1:12977`

●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

●Ensure proper origin isolation with COOP

●Mitigate DOM-based XSS with Trusted Types

●Page has valid source maps

○Redirects HTTP traffic to HTTPS

○Use a strong HSTS policy

○Mitigate clickjacking with XFO or CSP

○Detected JavaScript libraries

100

SEO

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

○Structured data is valid

●Page isn’t blocked from indexing

●Document has a `<title>` element

●Document has a meta description

●Page has successful HTTP status code

●Links have descriptive text

●Links are crawlable

●robots.txt is valid

●Image elements have `[alt]` attributes

●Document has a valid `hreflang`

●Document has a valid `rel=canonical`