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.

100

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.

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

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
llvm.org/img/LLVMWyvernSmall.png	0.0 ms	255.2 KiB
llvm.org/llvm.css	0.0 ms	1.5 KiB
llvm.org/img/lines.gif	0.0 ms	336 B

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
body > div.www_title > img `body > div.www_title > img`	llvm.org/img/LLVMWyvernSmall.png	254.9 KiB	253.4 KiB

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
llvm.org/llvm.css	1.5 KiB	151 ms

Tap interactions may be delayed by up to 300 ms if the viewport is not optimized for mobile.

Why this matters

Performance issues directly impact user engagement and conversion rates.

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

Diagnostics

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
body > div.www_title > img `body > div.www_title > img`	llvm.org/img/LLVMWyvernSmall.png

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

●Layout shift culprits

●Document request latency

●Optimize DOM size

●Font display

●Forced reflow

●LCP breakdown

●Modern HTTP

●Time to Interactive 0.9 s

●Max Potential First Input Delay 60 ms

●Minify CSS

●Minify JavaScript

●Reduce unused CSS

●Reduce unused JavaScript

●Avoids enormous network payloads Total size was 264 KiB

●JavaScript execution time 0.0 s

●Minimizes main-thread work 0.5 s

●Avoid long main-thread tasks 3 long tasks found

●Page didn't prevent back/forward cache restoration

●Network Requests

●Network Round Trip Times 150 ms

●Server Backend Latencies 0 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 150 ms

●Avoid large layout shifts 1 layout shift found

○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.

Internationalization and localization

If a page doesn't specify a `lang` attribute, a screen reader assumes that the page is in the default language that the user chose when setting up the screen reader. If the page isn't actually in the default language, then the screen reader might not announce the page's text correctly. Learn more about the `lang` attribute.

Why this matters

Performance issues directly impact user engagement and conversion rates.

Failing Elements
html `html`

These are opportunities to improve the interpretation of your content by users in different locales.

Names and labels

Informative elements should aim for short, descriptive alternate text. Decorative elements can be ignored with an empty alt attribute. Learn more about the `alt` attribute.

Why this matters

Performance issues directly impact user engagement and conversion rates.

Failing Elements
body > div.www_title > img `body > div.www_title > img`

Labels ensure that form controls are announced properly by assistive technologies, like screen readers. Learn more about form element labels.

Why this matters

Performance issues directly impact user engagement and conversion rates.

Failing Elements
div.www_sidebar > form > div > input `div.www_sidebar > form > div > input`

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

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
Overview `tr > td > div.www_sidebar > a`
Features `tr > td > div.www_sidebar > a`
Documentation `tr > td > div.www_sidebar > a`
Command Guide `tr > td > div.www_sidebar > a`
FAQ `tr > td > div.www_sidebar > a`
Publications `tr > td > div.www_sidebar > a`
LLVM Projects `tr > td > div.www_sidebar > a`
Open Projects `tr > td > div.www_sidebar > a`
LLVM Users `tr > td > div.www_sidebar > a`
Bug tracker `tr > td > div.www_sidebar > a`
LLVM Logo `tr > td > div.www_sidebar > a`
Blog `tr > td > div.www_sidebar > a`
Meetings `tr > td > div.www_sidebar > a`
LLVM Foundation `tr > td > div.www_sidebar > a`
All Releases `tr > td > div.www_sidebar > a`
APT Packages `tr > td > div.www_sidebar > a`
RPM Snapshots `tr > td > div.www_sidebar > a`
Pre-releases `tr > td > div.www_sidebar > a`
div.www_sidebar > form > div > input `div.www_sidebar > form > div > input`
div.www_sidebar > form > div > input `div.www_sidebar > form > div > input`
doxygen `tr > td > div.www_sidebar > a`
Sources (GitHub) `tr > td > div.www_sidebar > a`
Code Review `tr > td > div.www_sidebar > a`
Blog `tr > td > div.www_sidebar > a`
Bug tracker `tr > td > div.www_sidebar > a`
Buildbot `tr > td > div.www_sidebar > a`
Green Dragon `tr > td > div.www_sidebar > a`
LNT `tr > td > div.www_sidebar > a`
Scan-build `tr > td > div.www_sidebar > a`
llvm-cov `tr > td > div.www_sidebar > a`
All Announcements `td > div.www_sidebar > span > a`
October 27-29, 2025 `div.www_text > ul > li > a`
June 10, 2025 `div.www_text > ul > li > a`
April 14-16, 2025 `div.www_text > ul > li > a`
October 22-24, 2024 `div.www_text > ul > li > a`
April 10-11, 2024 `div.www_text > ul > li > a`
October 9-11, 2023 `div.www_text > ul > li > a`
May 10-11, 2023 `div.www_text > ul > li > a`
November 8-9, 2022 `div.www_text > ul > li > a`
May 10-11, 2022 `div.www_text > ul > li > a`
November 16-19, 2021 `div.www_text > ul > li > a`
October 6-8, 2020 `div.www_text > ul > li > a`
October 22-23, 2019 `div.www_text > ul > li > a`
April 8-9, 2019 `div.www_text > ul > li > a`
October 17-18, 2018 `div.www_text > ul > li > a`
April 16-17, 2018 `div.www_text > ul > li > a`
October 18-19, 2017 `div.www_text > ul > li > a`
March 27-28, 2017 `div.www_text > ul > li > a`
November 3-4, 2016 `div.www_text > ul > li > a`
March 17-18, 2016 `div.www_text > ul > li > a`
October 29-30, 2015 `div.www_text > ul > li > a`
April 13-14, 2015 `div.www_text > ul > li > a`
October 28-29, 2014 `div.www_text > ul > li > a`
April 7-8, 2014 `div.www_text > ul > li > a`
Nov 6-7, 2013 `div.www_text > ul > li > a`
April 29-30, 2013 `div.www_text > ul > li > a`
November 7-8, 2012 `div.www_text > ul > li > a`
April 12, 2012 `div.www_text > ul > li > a`
November 18, 2011 `div.www_text > ul > li > a`
September 2011 `div.www_text > ul > li > a`
November 2010 `div.www_text > ul > li > a`
October 2009 `div.www_text > ul > li > a`
August 2008 `div.www_text > ul > li > a`
May 2007 `div.www_text > ul > li > a`

One main landmark helps screen reader users navigate a web page. Learn more about landmarks.

Why this matters

Performance issues directly impact user engagement and conversion rates.

Failing Elements
html `html`

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

●Input buttons have discernible text.

●Background and foreground colors have a sufficient contrast ratio

●Document has a `<title>` element

●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

●Cells in a `<table>` element that use the `[headers]` attribute refer to table cells within the same table.

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

●Identical links have the same purpose.

○`[accesskey]` values are unique

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

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

○ARIA attributes are used as specified for the element's role

○Deprecated ARIA roles were not used

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

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

○ARIA input fields have accessible names

○ARIA `meter` elements have accessible names

○ARIA `progressbar` elements have accessible names

○Elements use only permitted ARIA attributes

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

○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

○`[role]` values are valid

○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

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

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

○Buttons have an accessible name

○`<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

○Heading elements appear in a sequentially-descending order

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

○`<html>` element has an `[xml:lang]` attribute with the same base language as the `[lang]` attribute.

○`<input type="image">` elements have `[alt]` text

○The document does not use `<meta http-equiv="refresh">`

○`[user-scalable="no"]` is not used in the `<meta name="viewport">` element and the `[maximum-scale]` attribute is not less than 5.

○`<object>` elements have alternate text

○Select elements have associated label elements.

○Skip links are focusable.

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

○`<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.

○Elements with visible text labels have matching accessible names.

○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.

100

Best Practices

●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 browser errors logged to the console

●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

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.

Informative elements should aim for short, descriptive alternate text. Decorative elements can be ignored with an empty alt attribute. Learn more about the `alt` attribute.

Why this matters

Performance issues directly impact user engagement and conversion rates.

Failing Elements
body > div.www_title > img `body > div.www_title > img`

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

●robots.txt is valid

●Document has a valid `hreflang`

○Document has a valid `rel=canonical`