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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.

81

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:0.214524] map[node:map[boundingRect:map[bottom:846 height:198 left:30 right:382 top:648 width:352] lhId:page-1-DIV nodeLabel:div.layout > div.video > div.container > div.video__embed path:1,HTML,1,BODY,2,DIV,1,DIV,0,DIV,0,DIV selector:div.layout > div.video > div.container > div.video__embed snippet:<div class="video__embed"> type:node] score:0.123265 subItems:map[items:[map[cause:Web font extra:map[type:url value:https://rubyonrails.org/assets/fonts/calibre-bold.woff2]] map[cause:Web font extra:map[type:url value:https://rubyonrails.org/assets/fonts/IBMPlexMono-Medium.woff2]]] type:subitems]] map[node:map[boundingRect:map[bottom:846 height:198 left:30 right:382 top:648 width:352] lhId:page-1-DIV nodeLabel:div.layout > div.video > div.container > div.video__embed path:1,HTML,1,BODY,2,DIV,1,DIV,0,DIV,0,DIV selector:div.layout > div.video > div.container > div.video__embed snippet:<div class="video__embed"> type:node] score:0.091259]]

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.

RequestCache TTLTransfer Size
videos.37signals.com/rails/rails-8-demo.mp43600.0 s1.1 MiB
videos.37signals.com/rails/rails-8-demo.webp3600.0 s420.1 KiB
rubyonrails.org/assets/fonts/IBMPlexMono-Medium.woff2600.0 s39.6 KiB
rubyonrails.org/assets/fonts/IBMPlexMono-Text.woff2600.0 s39.3 KiB
rubyonrails.org/assets/fonts/calibre-bold.woff2600.0 s26.8 KiB
rubyonrails.org/assets/fonts/calibre-semibold.woff2600.0 s26.1 KiB
rubyonrails.org/assets/fonts/calibre-regular.woff2600.0 s25.9 KiB
rubyonrails.org/assets/css/style.css600.0 s10.7 KiB
rubyonrails.org/assets/images/logo-soundcloud.svg600.0 s4.2 KiB
rubyonrails.org/assets/images/logo-airbnb.svg600.0 s4.0 KiB
rubyonrails.org/assets/images/logo-dribbble.svg600.0 s3.1 KiB
rubyonrails.org/assets/images/logo-shopify.svg600.0 s2.9 KiB
rubyonrails.org/assets/images/logo-hey.svg600.0 s2.6 KiB
rubyonrails.org/assets/images/logo-github.svg600.0 s2.6 KiB
rubyonrails.org/assets/images/logo-1password.svg600.0 s2.5 KiB
rubyonrails.org/assets/images/logo-intercom.svg600.0 s2.4 KiB
rubyonrails.org/assets/images/logo-basecamp.svg600.0 s2.2 KiB
rubyonrails.org/assets/images/logo-kickstarter.svg600.0 s2.2 KiB
rubyonrails.org/assets/images/logo-fleetio.svg600.0 s2.2 KiB
rubyonrails.org/assets/images/logo.svg600.0 s2.1 KiB
rubyonrails.org/assets/images/logo-coinbase.svg600.0 s2.0 KiB
rubyonrails.org/assets/images/logo-planetscale.svg600.0 s2.0 KiB
rubyonrails.org/assets/images/logo-lime.svg600.0 s2.0 KiB
rubyonrails.org/assets/images/logo-freeagent.svg600.0 s1.9 KiB
rubyonrails.org/assets/images/logo-cookpad.svg600.0 s1.8 KiB
rubyonrails.org/assets/images/logo-doximity.svg600.0 s1.7 KiB
rubyonrails.org/assets/images/logo-square.svg600.0 s1.7 KiB
rubyonrails.org/assets/images/logo-zendesk.svg600.0 s1.6 KiB
rubyonrails.org/assets/images/logo-instacart.svg600.0 s1.6 KiB
rubyonrails.org/assets/images/logo-gusto.svg600.0 s1.5 KiB
rubyonrails.org/assets/images/logo-heroku.svg600.0 s1.2 KiB
rubyonrails.org/assets/images/icon-button.svg600.0 s750 B
rubyonrails.org/assets/images/icon-card.svg600.0 s702 B
rubyonrails.org/assets/images/shape-top-up-left.svg600.0 s519 B
rubyonrails.org/assets/images/shape-top-down-left.svg600.0 s491 B
rubyonrails.org/assets/images/shape-bottom-up-left.svg600.0 s453 B
rubyonrails.org/assets/images/shape-top-down-right.svg600.0 s384 B
videos.37signals.com/rails/rails-8-demo.mp43600.0 s0 B
videos.37signals.com/rails/rails-8-demo.mp43600.0 s0 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.

URLResource SizeEst Savings
div.video > div.container > div.video__embed > video div.video > div.container > div.video__embed > video
videos.37signals.com/rails/rails-8-demo.webp419.5 KiB416.0 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.

URLTransfer SizeDuration
rubyonrails.org/assets/css/style.css10.7 KiB150 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.

ElementLayout shift score
div.layout > div.video > div.container > div.video__embed div.layout > div.video > div.container > div.video__embed
0.123
div.layout > div.video > div.container > div.video__embed div.layout > div.video > div.container > div.video__embed
0.091

The maximum potential First Input Delay that your users could experience is the duration of the longest task. Learn more about the Maximum Potential First Input Delay metric.

Why this matters

Performance issues directly impact user engagement and conversion rates.

Diagnostics

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
Other1.6 s
Style & Layout519 ms
Rendering325 ms
Script Evaluation65 ms
Parse HTML & CSS30 ms
Script Parsing & Compilation1.4 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
Basecamp div.trusted__blocks > div.trusted__block > a > img
rubyonrails.org/assets/images/logo-basecamp.svg
HEY div.trusted__blocks > div.trusted__block > a > img
rubyonrails.org/assets/images/logo-hey.svg
GitHub div.trusted__blocks > div.trusted__block > a > img
rubyonrails.org/assets/images/logo-github.svg
Shopify div.trusted__blocks > div.trusted__block > a > img
rubyonrails.org/assets/images/logo-shopify.svg
Instacart div.trusted__blocks > div.trusted__block > a > img
rubyonrails.org/assets/images/logo-instacart.svg
Dribbble div.trusted__blocks > div.trusted__block > a > img
rubyonrails.org/assets/images/logo-dribbble.svg
Gusto div.trusted__blocks > div.trusted__block > a > img
rubyonrails.org/assets/images/logo-gusto.svg
Zendesk div.trusted__blocks > div.trusted__block > a > img
rubyonrails.org/assets/images/logo-zendesk.svg
Airbnb div.trusted__blocks > div.trusted__block > a > img
rubyonrails.org/assets/images/logo-airbnb.svg
Square div.trusted__blocks > div.trusted__block > a > img
rubyonrails.org/assets/images/logo-square.svg
Kickstarter div.trusted__blocks > div.trusted__block > a > img
rubyonrails.org/assets/images/logo-kickstarter.svg
Heroku div.trusted__blocks > div.trusted__block > a > img
rubyonrails.org/assets/images/logo-heroku.svg
Coinbase div.trusted__blocks > div.trusted__block > a > img
rubyonrails.org/assets/images/logo-coinbase.svg
Soundcloud div.trusted__blocks > div.trusted__block > a > img
rubyonrails.org/assets/images/logo-soundcloud.svg
Cookpad div.trusted__blocks > div.trusted__block > a > img
rubyonrails.org/assets/images/logo-cookpad.svg
Doximity div.trusted__blocks > div.trusted__block > a > img
rubyonrails.org/assets/images/logo-doximity.svg
Intercom div.trusted__blocks > div.trusted__block > a > img
rubyonrails.org/assets/images/logo-intercom.svg
Fleetio div.trusted__blocks > div.trusted__block > a > img
rubyonrails.org/assets/images/logo-fleetio.svg
Lime div.trusted__blocks > div.trusted__block > a > img
rubyonrails.org/assets/images/logo-lime.svg
FreeAgent div.trusted__blocks > div.trusted__block > a > img
rubyonrails.org/assets/images/logo-freeagent.svg
1password div.trusted__blocks > div.trusted__block > a > img
rubyonrails.org/assets/images/logo-1password.svg
PlanetScale div.trusted__blocks > div.trusted__block > a > img
rubyonrails.org/assets/images/logo-planetscale.svg

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

●Document request latency
●Optimize DOM size
●Font display
●Forced reflow
●LCP breakdown
●Modern HTTP
●Optimize viewport for mobile
●Time to Interactive 1.6 s
●Minify CSS
●Minify JavaScript
●Reduce unused CSS
●Reduce unused JavaScript
●Avoids enormous network payloads Total size was 1,823 KiB
●JavaScript execution time 0.1 s
●Avoid long main-thread tasks 4 long tasks found
●Page didn't prevent back/forward cache restoration
●Network Requests
●Network Round Trip Times 0 ms
●Server Backend Latencies 150 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
97

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.

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
Ruby on Rails scales from PROMPT to IPO. Token-efficient code that's easy for a… div.container > div.heading__body > div.heading__headline > h4
Over the past two decades, Rails has taken countless companies to millions of u… div.container > div.heading__body > div.heading__headline > h4
Over six thousand people have contributed code to Rails, and many more have ser… div.container > div.heading__body > div.heading__headline > h4
Rails is a full-stack framework. It ships with all the tools needed to build am… div.container > div.heading__body > div.heading__headline > h4
app/models/article.rb div.example__body > div.example__block > div.example__code > h6
app/controllers/articles_controller.rb div.example__body > div.example__block > div.example__code > h6
app/views/articles/show.html.erb div.example__body > div.example__block > div.example__code > h6
config/routes.rb div.example__body > div.example__block > div.example__code > h6
LEARNING a > div.card__body > div.card__label > h6
CONTRIBUTING a > div.card__body > div.card__label > h6
KEEPING UP a > div.card__body > div.card__label > h6

These are opportunities to improve keyboard navigation in your application.

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-*]` 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
●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
●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
●Touch targets have sufficient size and spacing.
●Deprecated ARIA roles were not used
●Uses ARIA roles only on compatible elements
○`[accesskey]` values are unique
○`button`, `link`, and `menuitem` elements have accessible names
○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 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
○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
○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.
○Image elements do not have `[alt]` attributes that are redundant text.
○Identical links have the same purpose.
○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
●robots.txt is valid
●Image elements have `[alt]` attributes
●Document has a valid `hreflang`
○Document has a valid `rel=canonical`

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