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Lighthouse Mobile

· 0 checks — Mobile Lighthouse audit -- Performance, Accessibility, Best Practices, and SEO category breakdown.
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Detailed Report

Audit breakdown by category with detailed findings.

92

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
ffmpeg.org/fonts/fontawesome-webfont.woff?v=4.2.00.0 ms64.3 KiB
ffmpeg.org/img/coverity-lifetime-2024-08.PNG0.0 ms62.0 KiB
ffmpeg.org/js/jquery.min.js0.0 ms29.2 KiB
ffmpeg.org/css/bootstrap.min.css0.0 ms18.7 KiB
ffmpeg.org/js/bootstrap.min.js0.0 ms9.6 KiB
ffmpeg.org/css/font-awesome.min.css0.0 ms5.3 KiB
ffmpeg.org/css/style.min.css0.0 ms2.5 KiB
ffmpeg.org/img/ffmpeg3d_white_20.png0.0 ms995 B
ffmpeg.org/css/simple-sidebar.css0.0 ms932 B

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
ffmpeg.org/fonts/fontawesome-webfont.woff?v=4.2.095 ms

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
Coverity Lifetime Graph till 2024-08 div#page-content-wrapper > div.page-content > div#index > img
ffmpeg.org/img/coverity-lifetime-2024-08.PNG61.6 KiB55.7 KiB

HTTP/2 and HTTP/3 offer many benefits over HTTP/1.1, such as multiplexing. Learn more about using modern HTTP.

Why this matters

Performance issues directly impact user engagement and conversion rates.

URLProtocol
ffmpeg.org/http/1.1
ffmpeg.org/css/font-awesome.min.csshttp/1.1
ffmpeg.org/css/bootstrap.min.csshttp/1.1
ffmpeg.org/css/simple-sidebar.csshttp/1.1
ffmpeg.org/css/style.min.csshttp/1.1
ffmpeg.org/img/ffmpeg3d_white_20.pnghttp/1.1
ffmpeg.org/img/coverity-lifetime-2024-08.PNGhttp/1.1
ffmpeg.org/js/jquery.min.jshttp/1.1
ffmpeg.org/js/bootstrap.min.jshttp/1.1
ffmpeg.org/fonts/fontawesome-webfont.woff?v=4.2.0http/1.1
ffmpeg.org/favicon.icohttp/1.1

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
ffmpeg.org/js/jquery.min.js29.2 KiB906 ms
ffmpeg.org/css/style.min.css2.5 KiB456 ms
ffmpeg.org/css/simple-sidebar.css932 B456 ms
ffmpeg.org/css/bootstrap.min.css18.7 KiB756 ms
ffmpeg.org/css/font-awesome.min.css5.3 KiB156 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: 150 ms 17.6 KiB
URLTransfer SizeEst Savings
ffmpeg.org/css/bootstrap.min.css18.3 KiB17.6 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
Coverity Lifetime Graph till 2024-08 div#page-content-wrapper > div.page-content > div#index > img
ffmpeg.org/img/coverity-lifetime-2024-08.PNG
FFmpeg ul.sidebar-nav > li.sidebar-brand > a > img
ffmpeg.org/img/ffmpeg3d_white_20.png

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

●Time to Interactive 2.7 s
●Max Potential First Input Delay 90 ms
●Layout shift culprits
●Document request latency
●Optimize DOM size
●Forced reflow
●LCP breakdown
●Optimize viewport for mobile
●Minify CSS
●Minify JavaScript
●Reduce unused JavaScript
●Avoids enormous network payloads Total size was 254 KiB
●JavaScript execution time 0.0 s
●Minimizes main-thread work 0.4 s
●Avoid long main-thread tasks 2 long tasks found
●Page didn't prevent back/forward cache restoration
●Network Requests
●Network Round Trip Times 50 ms
●Server Backend Latencies 10 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 60 ms
○INP breakdown
○LCP request discovery
○User Timing marks and measures
○Avoid non-composited animations
○Avoid large layout shifts
73

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
Download div.row > div.col-md-6 > div.btn-download-wrapper > a.btn
Discover more div#index > div.well > div.text-right > a.btn
Past news div.page-content > div#index > div.text-right > a.btn

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.

Why this matters

Performance issues directly impact user engagement and conversion rates.

Failing Elements
FFmpeg 8.1 "Hoare" div.page-content > div#index > p > a
Khronos blog div.page-content > div#index > p > a
FFmpeg 8.0 "Huffman" div.page-content > div#index > p > a
Vulkan decoding div.page-content > div#index > p > a
code.ffmpeg.org div.page-content > div#index > p > a
FFmpeg 7.1 "Péter" div.page-content > div#index > p > a
changelog div.page-content > div#index > p > a
Coverity (a static analyzer) div.page-content > div#index > p > a
Sovereign Tech Fund div.page-content > div#index > p > a
Sovereign Tech Fund div.page-content > div#index > p > a
FFmpeg 7.0 "Dijkstra" div.page-content > div#index > p > a
native VVC decoder div.page-content > div#index > p > a
IAMF support div.page-content > div#index > p > a
multi-threaded ffmpeg CLI tool div.page-content > div#index > p > a
Changelog div.page-content > div#index > p > a
APIchanges div.page-content > div#index > p > a
IAMF div.page-content > div#index > p > a
FFmpeg 6.1 "Heaviside" div.page-content > div#index > p > a
documentation page div.page-content > div#index > p > a
repository div.page-content > div#index > p > a
FFmpeg 6.0 "Von Neumann" div.page-content > div#index > p > a
FFmpeg 5.1 "Riemann" div.page-content > div#index > p > a
FFmpeg 5.0 "Lorentz" div.page-content > div#index > p > a
contact#IRCChannels div.page-content > div#index > p > a
FFmpeg 4.4 "Rao" div.page-content > div#index > p > a
FFmpeg 4.3 "4:3" div.page-content > div#index > p > a
Incredibles 2 Screen Slaver div.page-content > div#index > p > a
trac div.page-content > div#index > p > a
See for yourself div.page-content > div#index > p > a
please let me know div.page-content > div#index > p > a
since 2013 div.page-content > div#index > p > a
FFmpeg 4.2 "Ada" div.page-content > div#index > p > a
FFmpeg 4.1 "al-Khwarizmi" div.page-content > div#index > p > a
FFmpeg 4.0 "Wu" div.page-content > div#index > p > a
FFmpeg 3.4 "Cantor" div.page-content > div#index > p > a
FFmpeg 3.3 "Hilbert" div.page-content > div#index > p > a
FFmpeg 3.1.2 div.page-content > div#index > p > a
FFmpeg 3.1.1 div.page-content > div#index > p > a
FFmpeg 3.1 "Laplace" div.page-content > div#index > p > a
Google Summer of Code div.page-content > div#index > p > a
project ideas page div.page-content > div#index > p > a
FFmpeg 3.0 "Einstein" div.page-content > div#index > p > a
Changelog div#index > ul > li > a
stable div.page-content > div#index > p > a
Kamedo2 div.page-content > div#index > p > a
bug tracker div.page-content > div#index > p > a
Telepoint ul > li > p > a
Google Summer of Code div.page-content > div#index > p > a
Google div.page-content > div#index > p > a
VideoLAN Developer Days div.page-content > div#index > p > a
FFmpeg div.page-content > div#index > p > a
MPlayer div.page-content > div#index > p > a
rtmpdump div.page-content > div#index > p > a
ffmpeg-devel div.page-content > div#index > p > a
trac div.page-content > div#index > p > a
samples repo div.page-content > div#index > p > a
Google Summer of Code div.page-content > div#index > p > a
project ideas page div.page-content > div#index > p > a
here div.page-content > div#index > p > a
here div.page-content > div#index > p > a
FFmpeg packages in Debian unstable div.page-content > div#index > p > a
Read the argumentation over at Debian. div.page-content > div#index > p > a
OPW wiki page div.page-content > div#index > p > a
Click&Pledge div.page-content > div#index > p > a
e-mail div.page-content > div#index > p > a
db0 div.page-content > div#index > p > a
OPW div.page-content > div#index > p > a
email address div.page-content > div#index > p > a
security issue in the LZO implementation div.page-content > div#index > p > a
here div.page-content > div#index > p > a
archive div.page-content > div#index > p > a
"OpenSSL heartbleed" div.page-content > div#index > p > a
here div.page-content > div#index > p > a
Rogério Brito div.page-content > div#index > p > a
ticket #729203 div.page-content > div#index > p > 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
March 16th, 2026, FFmpeg 8.1 "Hoare" div#page-content-wrapper > div.page-content > div#index > h3#pr8.1

These are opportunities to improve keyboard navigation in your application.

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.

Why this matters

Performance issues directly impact user engagement and conversion rates.

Failing Elements
div#page-content-wrapper > header.content-header > h1 > a#menu-toggle div#page-content-wrapper > header.content-header > h1 > a#menu-toggle
div#index > h1#news > span.pull-right > a div#index > h1#news > span.pull-right > a
div#index > h1#news > span.pull-right > a div#index > h1#news > span.pull-right > a
div#index > h1#news > span.pull-right > a div#index > h1#news > span.pull-right > a

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

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>`
●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.
●Document has a `<title>` element
●`<html>` element has a `[lang]` attribute
●`<html>` element has a valid value for its `[lang]` attribute
●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.
●Image elements do not have `[alt]` attributes that are redundant text.
●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
○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.
○Skip links are focusable.
○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
○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 DOM-based XSS with Trusted Types
●Detected JavaScript libraries
●Page has valid source maps
○Redirects HTTP traffic to HTTPS
○Mitigate clickjacking with XFO or CSP
83

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.

Descriptive link text helps search engines understand your content. Learn how to make links more accessible.

Why this matters

Performance issues directly impact user engagement and conversion rates.

Link destinationLink Text
chemnitzer.linux-tage.de/2015/en/here
chemnitzer.linux-tage.de/2015/de/programm/beitrag/209here
www.linuxtag.org/2014/here
chemnitzer.linux-tage.de/2014/en/info/here

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 are crawlable
●robots.txt is valid
●Image elements have `[alt]` attributes
●Document has a valid `hreflang`
○Document has a valid `rel=canonical`

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