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.

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
/3AaSu3zE/qBvsWf4/ZlJ9obh/Hu/fiapbzJb3i0N8h7Dip/SF4jOnQD/...	21600.0 s	173.8 KiB
openjdk.org/.fonts/DejaVuSans-webfont.woff	18641.0 s	21.4 KiB
openjdk.org/.fonts/DejaVuSans-Bold-webfont.woff	29953.0 s	21.4 KiB
openjdk.org/images/duke-thinking.png	20871.0 s	14.8 KiB
openjdk.org/images/duke-pipes.png	20871.0 s	12.6 KiB
openjdk.org/akam/13/3ce02fab	21600.0 s	9.3 KiB
openjdk.org/images/duke-plug.png	48106.0 s	11.7 KiB
openjdk.org/images/duke-chalkboard.png	48106.0 s	8.8 KiB
openjdk.org/images/oracle.svg	18641.0 s	2.3 KiB
openjdk.org/images/openjdk2.svg	69333.0 s	2.3 KiB
openjdk.org/page.js	18641.0 s	1.1 KiB
openjdk.org/page.css	86400.0 s	1.6 KiB
openjdk.org/.fonts/dejavu.css	86400.0 s	1.2 KiB

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
Duke thinking `tbody > tr > td > img`	openjdk.org/images/duke-thinking.png	14.3 KiB	13.4 KiB
Duke hacking `tbody > tr > td > img`	openjdk.org/images/duke-pipes.png	12.0 KiB	11.5 KiB
Duke plugging `tbody > tr > td > img`	openjdk.org/images/duke-plug.png	11.2 KiB	10.2 KiB
Duke chalkboard `tbody > tr > td > img`	openjdk.org/images/duke-chalkboard.png	8.3 KiB	7.6 KiB

Each subpart has specific improvement strategies. Ideally, most of the LCP time should be spent on loading the resources, not within delays.

Why this matters

Performance issues directly impact user engagement and conversion rates.

headings: [map[key:label label:Subpart valueType:text] map[key:duration label:Duration valueType:ms]]

items: [map[duration:380.483 label:Time to first byte subpart:timeToFirstByte] map[duration:2178.709 label:Element render delay subpart:elementRenderDelay]]

lhId: page-4-TD

nodeLabel: Download and install the latest open-source JDK. Oracle’s free, GPL-licensed, p…

path: 1,HTML,1,BODY,0,DIV,1,TABLE,0,TBODY,1,TR,1,TD

selector: table.main > tbody > tr > td

snippet: <td>

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

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
openjdk.org/.fonts/DejaVuSans-webfont.woff	10 ms
openjdk.org/.fonts/DejaVuSans-Bold-webfont.woff	10 ms

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
openjdk.org/page.css	1.6 KiB
openjdk.org/.fonts/dejavu.css	1.2 KiB
openjdk.org/page.js	1.1 KiB

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

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: 150 ms 37.0 KiB

URL	Transfer Size	Est Savings
/3AaSu3zE/qBvsWf4/ZlJ9obh/Hu/fiapbzJb3i0N8h7Dip/SF4jOnQD/...	172.9 KiB	37.0 KiB

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

Why this matters

Performance issues directly impact user engagement and conversion rates.

Failure reason	Failure type
The page was evicted from back/forward cache because an active network request involved a redirect.	Not actionable

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
Duke plugging `tbody > tr > td > img`	openjdk.org/images/duke-plug.png
Duke thinking `tbody > tr > td > img`	openjdk.org/images/duke-thinking.png
Duke chalkboard `tbody > tr > td > img`	openjdk.org/images/duke-chalkboard.png
Duke hacking `tbody > tr > td > img`	openjdk.org/images/duke-pipes.png

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

●Max Potential First Input Delay 120 ms

●Time to Interactive 3.3 s

●Layout shift culprits

●Document request latency

●Optimize DOM size

●Forced reflow

●Modern HTTP

●Minify CSS

●Minify JavaScript

●Reduce unused CSS

●Avoids enormous network payloads Total size was 295 KiB

●JavaScript execution time 0.8 s

●Minimizes main-thread work 1.1 s

●Avoid long main-thread tasks 5 long tasks found

●Network Requests

●Network Round Trip Times 0 ms

●Server Backend Latencies 80 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 310 ms

○INP breakdown

○LCP request discovery

○User Timing marks and measures

○Avoid non-composited animations

○Avoid large layout shifts

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
(overview, archive) `body > div#sidebar > div.links > div.link`
(overview, archive) `body > div#sidebar > div.links > div.link`
JDK (…, 25, 26, 27) `body > div#sidebar > div.links > div.link`
© 2026 Oracle Corporation and/or its affiliates Terms of Use · License: GPLv2 ·… `body > div#footer`
Terms of Use `body > div#footer > a`
GPLv2 `body > div#footer > a`
Privacy `body > div#footer > a`
Trademarks `body > div#footer > a`

These are opportunities to improve the legibility of your content.

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

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
OpenJDK logo `body > div#sidebar > div#openjdk-sidebar-logo > 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

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
Installing `div#sidebar > div.links > div.link > a`
Contributing `div#sidebar > div.links > div.link > a`
Sponsoring `div#sidebar > div.links > div.link > a`
Developers' Guide `div#sidebar > div.links > div.link > a`
Vulnerabilities `div#sidebar > div.links > div.link > a`
JDK GA/EA Builds `div#sidebar > div.links > div.link > a`
Mailing lists `div#sidebar > div.links > div.links > a`
Mastodon `div#sidebar > div.links > div.link > a`
Bluesky `div#sidebar > div.links > div.link > a`
Workshop `div#sidebar > div.links > div.links > a`
JEP Process `div#sidebar > div.links > div.links > a`
GitHub `div#sidebar > div.links > div.link > a`
Mercurial `div#sidebar > div.links > div.link > a`
Git `div#sidebar > div.links > div.link > a`
Adoption `div#sidebar > div.links > div.link > a`
Build `div#sidebar > div.links > div.link > a`
Client Libraries `div#sidebar > div.links > div.link > a`
Compiler `div#sidebar > div.links > div.link > a`
Conformance `div#sidebar > div.links > div.link > a`
Core Libraries `div#sidebar > div.links > div.link > a`
Governing Board `div#sidebar > div.links > div.link > a`
HotSpot `div#sidebar > div.links > div.link > a`
IDE Tooling & Support `div#sidebar > div.links > div.link > a`
Internationalization `div#sidebar > div.links > div.link > a`
Members `div#sidebar > div.links > div.link > a`
Networking `div#sidebar > div.links > div.link > a`
Porters `div#sidebar > div.links > div.link > a`
Quality `div#sidebar > div.links > div.link > a`
Security `div#sidebar > div.links > div.link > a`
Serviceability `div#sidebar > div.links > div.link > a`
Vulnerability `div#sidebar > div.links > div.link > a`
Web `div#sidebar > div.links > div.link > a`
Amber `div#sidebar > div.links > div.link > a`
Babylon `div#sidebar > div.links > div.link > a`
Brisbane `div#sidebar > div.links > div.link > a`
CRaC `div#sidebar > div.links > div.link > a`
Code Tools `div#sidebar > div.links > div.link > a`
Coin `div#sidebar > div.links > div.link > a`
Common VM Interface `div#sidebar > div.links > div.link > a`
Detroit `div#sidebar > div.links > div.link > a`
Duke `div#sidebar > div.links > div.link > a`
Graal `div#sidebar > div.links > div.link > a`
IcedTea `div#sidebar > div.links > div.link > a`
JDK 8 Updates `div#sidebar > div.links > div.link > a`
JDK 9 `div#sidebar > div.links > div.link > a`
JDK Updates `div#sidebar > div.links > div.link > a`
JMC `div#sidebar > div.links > div.link > a`
Jigsaw `div#sidebar > div.links > div.link > a`
Lanai `div#sidebar > div.links > div.link > a`
Leyden `div#sidebar > div.links > div.link > a`
Lilliput `div#sidebar > div.links > div.link > a`
Loom `div#sidebar > div.links > div.link > a`
Memory Model Update `div#sidebar > div.links > div.link > a`
Metropolis `div#sidebar > div.links > div.link > a`
Multi-Language VM `div#sidebar > div.links > div.link > a`
Nashorn `div#sidebar > div.links > div.link > a`
New I/O `div#sidebar > div.links > div.link > a`
OpenJFX `div#sidebar > div.links > div.link > a`
Panama `div#sidebar > div.links > div.link > a`
Port: AArch32 `div#sidebar > div.links > div.link > a`
Port: AArch64 `div#sidebar > div.links > div.link > a`
Port: BSD `div#sidebar > div.links > div.link > a`
Port: Haiku `div#sidebar > div.links > div.link > a`
Port: MIPS `div#sidebar > div.links > div.link > a`
Port: Mobile `div#sidebar > div.links > div.link > a`
Port: PowerPC/AIX `div#sidebar > div.links > div.link > a`
Port: RISC-V `div#sidebar > div.links > div.link > a`
Port: s390x `div#sidebar > div.links > div.link > a`
SCTP `div#sidebar > div.links > div.link > a`
Shenandoah `div#sidebar > div.links > div.link > a`
Skara `div#sidebar > div.links > div.link > a`
Sumatra `div#sidebar > div.links > div.link > a`
Tsan `div#sidebar > div.links > div.link > a`
Valhalla `div#sidebar > div.links > div.link > a`
Wakefield `div#sidebar > div.links > div.link > a`
Zero `div#sidebar > div.links > div.link > a`
ZGC `div#sidebar > div.links > div.link > 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>`

●Image elements have `[alt]` attributes

●Document has a `<title>` element

●Links are distinguishable without relying on color.

●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.

●Tables use `<caption>` instead of cells with the `[colspan]` attribute to indicate a caption.

○`[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 buttons have discernible text.

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

○Form elements have associated labels

○Lists contain only `<li>` elements and script supporting elements (`<script>` and `<template>`).

○List items (`<li>`) are contained within `<ul>`, `<ol>` or `<menu>` parent elements

○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.

○`<td>` elements in a large `<table>` have one or more table headers.

Best Practices

User Experience

Image natural dimensions should be proportional to the display size and the pixel ratio to maximize image clarity. Learn how to provide responsive images.

Why this matters

Performance issues directly impact user engagement and conversion rates.

	URL	Displayed size	Actual size	Expected size
Duke plugging `tbody > tr > td > img`	openjdk.org/images/duke-plug.png	70 x 82	70 x 82	105 x 123
Duke thinking `tbody > tr > td > img`	openjdk.org/images/duke-thinking.png	70 x 72	70 x 72	105 x 108
Duke chalkboard `tbody > tr > td > img`	openjdk.org/images/duke-chalkboard.png	70 x 61	70 x 61	105 x 92
Duke hacking `tbody > tr > td > img`	openjdk.org/images/duke-pipes.png	70 x 47	70 x 47	105 x 71

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
openjdk.report-uri.com/r/default/csp/reportOnly	`Failed to load resource: net::ERR_FAILED`
openjdk.report-uri.com/r/default/csp/reportOnly	`Failed to load resource: net::ERR_FAILED`
openjdk.report-uri.com/r/default/csp/reportOnly	`Failed to load resource: net::ERR_FAILED`
openjdk.org/page.js line 27, col 20	`TypeError: Cannot set properties of null (setting 'onfocus') at window.onload (https://openjdk.org/page.js:28:21)`

Issues logged to the `Issues` panel in Chrome Devtools indicate unresolved problems. They can come from network request failures, insufficient security controls, and other browser concerns. Open up the Issues panel in Chrome DevTools for more details on each issue.

Why this matters

Performance issues directly impact user engagement and conversion rates.

Issue type
Content security policy

Source maps translate minified code to the original source code. This helps developers debug in production. In addition, Lighthouse is able to provide further insights. Consider deploying source maps to take advantage of these benefits. Learn more about source maps.

Why this matters

Performance issues directly impact user engagement and conversion rates.

URL
/3AaSu3zE/qBvsWf4/ZlJ9obh/Hu/fiapbzJb3i0N8h7Dip/SF4jOnQD/...

●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

●Page has the HTML doctype

●Properly defines charset

●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

○Redirects HTTP traffic to HTTPS

○Mitigate clickjacking with XFO or CSP

○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.

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 destination	Link Text
www.oracle.com/java/technologies/downloads/	here

Format your HTML in a way that enables crawlers to better understand your app’s content.

Crawling and Indexing

If your robots.txt file is malformed, crawlers may not be able to understand how you want your website to be crawled or indexed. Learn more about robots.txt.

Why this matters

Performance issues directly impact user engagement and conversion rates.

To appear in search results, crawlers need access to your app.

○Structured data is valid

●Page isn’t blocked from indexing

●Document has a `<title>` element

●Page has successful HTTP status code

●Links are crawlable

●Image elements have `[alt]` attributes

●Document has a valid `hreflang`

○Document has a valid `rel=canonical`