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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.

54

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.

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:24.361 label:Time to first byte subpart:timeToFirstByte] map[duration:3211.991 label:Element render delay subpart:elementRenderDelay]]
lhId: page-0-PRE
nodeLabel: # Output "I love Ruby" say = "I love Ruby" puts say # Output "I *LOVE* RUBY" s…
path: 1,HTML,1,BODY,1,DIV,2,DIV,4,SECTION,0,DIV,1,DIV,0,DIV,1,DIV,1,DIV,0,FIGURE,0,PRE
selector: div.code-example-wrapper > div#try-ruby-example-1 > figure.highlight > pre
snippet: <pre>

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
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
/css2?family=Noto+Sans+JP:wght@100..900&family=Noto+Sans+...116.5 KiB1.4 s
www.ruby-lang.org/stylesheets/compiled.css17.3 KiB300 ms
fonts.googleapis.com/css2?family=Noto+Sans:wght@400;700&display=swap867 B
www.ruby-lang.org/javascripts/try-ruby-examples.js1.3 KiB

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
www.ruby-lang.org/images/home/why_ruby/pragdave.jpeg600.0 s412.4 KiB
www.ruby-lang.org/images/home/why_ruby/dhh.jpeg600.0 s27.2 KiB
www.ruby-lang.org/images/home/why_ruby/matz.jpeg600.0 s21.7 KiB
www.ruby-lang.org/images/home/hero/illust-main/train.svg600.0 s18.3 KiB
www.ruby-lang.org/stylesheets/compiled.css600.0 s17.3 KiB
www.ruby-lang.org/images/home/hero/illust-sub.svg600.0 s15.9 KiB
www.ruby-lang.org/images/footer/illust-pattern.svg600.0 s14.2 KiB
www.ruby-lang.org/images/home/hero/sunburst.svg600.0 s8.5 KiB
www.ruby-lang.org/images/home/hero/illust-main/fire.svg600.0 s8.1 KiB
www.ruby-lang.org/images/home/why_ruby/amanda.jpeg600.0 s7.5 KiB
www.ruby-lang.org/images/home/hero/illust-main/boxes.svg600.0 s7.3 KiB
www.ruby-lang.org/images/footer/happy-hacking.svg600.0 s6.1 KiB
www.ruby-lang.org/images/home/hero/illust-main/ivan.svg600.0 s5.5 KiB
www.ruby-lang.org/images/home/hero/illust-main/sheep.svg600.0 s5.1 KiB
www.ruby-lang.org/images/home/hero/illust-main/justin.svg600.0 s4.6 KiB
www.ruby-lang.org/images/home/hero/illust-main/keyboard.svg600.0 s4.3 KiB
www.ruby-lang.org/images/home/hero/illust-main/coffee.svg600.0 s3.8 KiB
www.ruby-lang.org/images/home/hero/illust-main/mimi.svg600.0 s3.3 KiB
www.ruby-lang.org/images/home/hero/illust-main/spitz.svg600.0 s3.2 KiB
www.ruby-lang.org/images/home/hero/illust-main/game.svg600.0 s2.8 KiB
www.ruby-lang.org/images/home/hero/illust-main/beanie.svg600.0 s2.8 KiB
www.ruby-lang.org/images/home/hero/illust-main/robot.svg600.0 s2.8 KiB
www.ruby-lang.org/images/home/hero/illust-main/kevin.svg600.0 s2.7 KiB
www.ruby-lang.org/javascripts/hero-animation.js600.0 s2.6 KiB
www.ruby-lang.org/images/home/hero/illust-main/mary.svg600.0 s2.6 KiB
www.ruby-lang.org/images/home/hero/illust-main/daisy.svg600.0 s2.5 KiB
www.ruby-lang.org/images/home/hero/illust-main/max.svg600.0 s2.5 KiB
www.ruby-lang.org/images/home/hero/illust-main/beer.svg600.0 s2.3 KiB
www.ruby-lang.org/images/home/hero/illust-main/matz.svg600.0 s2.3 KiB
www.ruby-lang.org/images/home/hero/illust-main/yukiko.svg600.0 s1.9 KiB
www.ruby-lang.org/images/home/hero/illust-main/ink.svg600.0 s1.8 KiB
www.ruby-lang.org/images/home/hero/illust-main/present.svg600.0 s1.8 KiB
www.ruby-lang.org/javascripts/toc.js600.0 s1.7 KiB
www.ruby-lang.org/images/home/hero/illust-main/gem06.svg600.0 s1.7 KiB
www.ruby-lang.org/images/home/hero/illust-main/cat.svg600.0 s1.7 KiB
www.ruby-lang.org/images/home/hero/illust-main/dachs.svg600.0 s1.6 KiB
www.ruby-lang.org/images/home/hero/illust-main/pen.svg600.0 s1.6 KiB
www.ruby-lang.org/images/header-ruby-logo.svg600.0 s1.6 KiB
www.ruby-lang.org/javascripts/try-ruby-examples.js600.0 s1.3 KiB
www.ruby-lang.org/images/home/hero/illust-main/gem07.svg600.0 s1.1 KiB
www.ruby-lang.org/images/home/hero/illust-main/gem05.svg600.0 s1.1 KiB
www.ruby-lang.org/images/home/hero/illust-main/gem03.svg600.0 s1.1 KiB
www.ruby-lang.org/javascripts/theme-toggle.js600.0 s1.1 KiB
www.ruby-lang.org/images/home/hero/illust-main/gem02.svg600.0 s1.0 KiB
www.ruby-lang.org/images/home/hero/illust-main/gem08.svg600.0 s907 B
www.ruby-lang.org/javascripts/navigation-toggle.js600.0 s855 B
www.ruby-lang.org/javascripts/header-navigation.js600.0 s820 B
www.ruby-lang.org/images/home/hero/illust-main/gem01.svg600.0 s755 B
www.ruby-lang.org/images/home/hero/bg-ruby.svg600.0 s527 B
www.ruby-lang.org/images/home/why_ruby/line.svg600.0 s427 B
www.ruby-lang.org/images/home/hero/version-line.svg600.0 s386 B

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

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: 794 ms
URLTime Spent
www.ruby-lang.org/794 ms
www.ruby-lang.org/en/0.0 ms

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

Minifying CSS files can reduce network payload sizes. Learn how to minify CSS.

Why this matters

Performance issues directly impact user engagement and conversion rates.

Estimated savings: 160 ms 12.3 KiB
URLTransfer SizeEst Savings
/css2?family=Noto+Sans+JP:wght@100..900&family=Noto+Sans+...116.5 KiB12.3 KiB

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: 640 ms 128.8 KiB
URLTransfer SizeEst Savings
/css2?family=Noto+Sans+JP:wght@100..900&family=Noto+Sans+...116.1 KiB116.1 KiB
www.ruby-lang.org/stylesheets/compiled.css17.1 KiB12.7 KiB

Large network payloads cost users real money and are highly correlated with long load times. Learn how to reduce payload sizes.

Why this matters

Performance issues directly impact user engagement and conversion rates.

URLTransfer Size
/s/materialsymbolsrounded/v325/sykO-zNym6YjUruM-QrEh7-nyT...1.8 MiB
www.ruby-lang.org/images/home/why_ruby/pragdave.jpeg412.4 KiB
/css2?family=Noto+Sans+JP:wght@100..900&family=Noto+Sans+...116.5 KiB
/s/notosanstc/v39/-nF7OG829Oofr2wohFbTp9iFOisNA_cTyNromxq...83.1 KiB
/s/notosanssc/v40/k3kXo84MPvpLmixcA63oeALhLIiP-Q-87KaAaH7...74.9 KiB
/s/notosanstc/v39/-nF7OG829Oofr2wohFbTp9iFOisNA_cTyNromxq...58.8 KiB
/s/notosanssc/v40/k3kXo84MPvpLmixcA63oeALhLIiP-Q-87KaAaH7...51.3 KiB
/s/notosanssc/v40/k3kXo84MPvpLmixcA63oeALhLIiP-Q-87KaAaH7...45.1 KiB
/s/notosanstc/v39/-nF7OG829Oofr2wohFbTp9iFOisNA_cTyNromxq...33.8 KiB
/s/plusjakartasans/v12/LDIuaomQNQcsA88c7O9yZ4KMCoOg4Koz4y...28.9 KiB

Consider reducing the time spent parsing, compiling and executing JS. You may find delivering smaller JS payloads helps with this. Learn how to minimize main-thread work

Why this matters

Performance issues directly impact user engagement and conversion rates.

CategoryTime Spent
Other1.2 s
Style & Layout1.0 s
Rendering395 ms
Script Evaluation182 ms
Parse HTML & CSS72 ms
Script Parsing & Compilation7.6 ms

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
Happy Hacking! div.container > div.flex > div.mb-3 > img.h-24
www.ruby-lang.org/images/footer/happy-hacking.svg

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
●Improve image delivery
●Modern HTTP
●Optimize viewport for mobile
●Max Potential First Input Delay 20 ms
●Minify JavaScript
●Reduce unused JavaScript
●JavaScript execution time 0.2 s
●Avoid long main-thread tasks 5 long tasks found
●Page didn't prevent back/forward cache restoration
●Network Requests
●Network Round Trip Times 10 ms
●Server Backend Latencies 40 ms
●Tasks
●Diagnostics
●Metrics
●Screenshot Thumbnails
●Final Screenshot
●Script Treemap Data
●Resources Summary
●Initial server response time was short Root document took 20 ms
●Avoid large layout shifts 3 layout shifts found
○INP breakdown
○LCP request discovery
○User Timing marks and measures
○Avoid non-composited animations
88

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.

Names and labels

When a button doesn't have an accessible name, screen readers announce it as "button", making it unusable for users who rely on screen readers. Learn how to make buttons more accessible.

Why this matters

Performance issues directly impact user engagement and conversion rates.

Failing Elements
div.container > div.flex > div.flex > button#mobile-menu-toggle div.container > div.flex > div.flex > button#mobile-menu-toggle

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.

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.absolute > div.absolute > div.flex > a.mt-4
# Output "I love Ruby" figure.highlight > pre > code.language-ruby > span.c1
puts figure.highlight > pre > code.language-ruby > span.nb
# Output "I *LOVE* RUBY" figure.highlight > pre > code.language-ruby > span.c1
puts figure.highlight > pre > code.language-ruby > span.nb
# Output "I *love* Ruby" figure.highlight > pre > code.language-ruby > span.c1
# five times figure.highlight > pre > code.language-ruby > span.c1
puts figure.highlight > pre > code.language-ruby > span.nb
# Ruby knows what you figure.highlight > pre > code.language-ruby > span.c1
# mean, even if you figure.highlight > pre > code.language-ruby > span.c1
# want to do math on figure.highlight > pre > code.language-ruby > span.c1
# an entire Array figure.highlight > pre > code.language-ruby > span.c1
puts figure.highlight > pre > code.language-ruby > span.nb
# The Greeter class figure.highlight > pre > code.language-ruby > span.c1
name figure.highlight > pre > code.language-ruby > span.nb
name figure.highlight > pre > code.language-ruby > span.nb
puts figure.highlight > pre > code.language-ruby > span.nb
# Create a new object figure.highlight > pre > code.language-ruby > span.c1
# Output "Hello World!" figure.highlight > pre > code.language-ruby > span.c1
Try Ruby div.container > div.text-center > p.text-stone-700 > a.text-semantic-text-link
Ecosystem div.why-ruby-card > div.relative > div.relative > h3.text-5xl
Creator of Ruby div.relative > div.flex-shrink-0 > div.text-left > p.text-xs
Simple div.why-ruby-card > div.relative > div.relative > h3.text-5xl
Creator of Ruby on Rails div.relative > div.flex-shrink-0 > div.text-left > p.text-xs
Productivity div.why-ruby-card > div.relative > div.relative > h3.text-5xl
Author of "The Pragmatic Programmer" div.relative > div.flex-shrink-0 > div.text-left > p.text-xs
Community div.why-ruby-card > div.relative > div.relative > h3.text-5xl
Executive Director of Rails Foundation div.relative > div.flex-shrink-0 > div.text-left > p.text-xs
The universal motto is "MINASWAN" — Matz is nice and so we are nice section.community-section > div.container > div.text-center > p.text-lg
MINASWAN div.container > div.text-center > p.text-lg > span.font-bold
Matz is nice and so we are nice div.container > div.text-center > p.text-lg > span.italic
Continue Reading... div.space-y-6 > article.pb-6 > p.mt-1 > a.text-xs
Continue Reading... div.space-y-6 > article.pb-6 > p.mt-1 > a.text-xs
Continue Reading... div.space-y-6 > article.pb-6 > p.mt-1 > a.text-xs
Continue Reading... div.space-y-6 > article.pb-6 > p.mt-1 > a.text-xs
Read more news div.grid > div.lg:col-span-2 > p.mt-4 > a.text-sm
Read more security div.grid > div > p.mt-4 > a.text-sm

These are opportunities to improve the legibility of your content.

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.fonts-loaded html.fonts-loaded

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>`
●`[aria-*]` attributes have valid values
●`[aria-*]` attributes are valid and not misspelled
●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.
●Heading elements appear in a sequentially-descending order
●Image elements do not have `[alt]` attributes that are redundant text.
●Identical links have the same purpose.
○`[accesskey]` values are unique
○`button`, `link`, and `menuitem` elements have accessible names
○Deprecated ARIA roles were not used
○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
○`[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
○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 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
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
●Image elements have `[alt]` attributes
●Document has a valid `hreflang`
●Document has a valid `rel=canonical`
○robots.txt is valid

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