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

Audit breakdown by category with detailed findings.

72

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
cdn.peerj.com/cb040aa/webpack/peerj-app.6cc34b02.js0.0 ms623.1 KiB
/images/journal-home/headers/PeerJ-Comp-Sci-Journal-Home-...0.0 ms446.6 KiB
/images/journal-home/headers/PeerJ-Journal-Home-950w.jpg0.0 ms381.5 KiB
cdn.peerj.com/cb040aa/webpack/fonts/materialdesignicons-webfont.bc2c1f6a.woff20.0 ms284.2 KiB
d2pdyyx74uypu5.cloudfront.net/images/home/PeerJHomepageSplash-1908x450.jpg0.0 ms139.5 KiB
cdn.peerj.com/cb040aa/webpack/330.a5145fec.js0.0 ms131.1 KiB
transcend-cdn.com/cm/ef49a3f1-d8c1-47d6-88fc-50e41130631f/tcf/ui.js60.0 s84.7 KiB
cdn.peerj.com/cb040aa/webpack/peerj-app.8ae05dc6.css0.0 ms79.3 KiB
transcend-cdn.com/cm/ef49a3f1-d8c1-47d6-88fc-50e41130631f/airgap.js60.0 s77.7 KiB
peerj.com/js/f67db00-8264f27.js14400.0 s93.4 KiB
peerj.com/js/8d39319-582a9a0.js14400.0 s74.9 KiB
cdn.peerj.com/cb040aa/webpack/330.3c2c95ca.css0.0 ms45.5 KiB
peerj.com/css/01fda25-aa54668.css14400.0 s44.3 KiB
cdn.mxpnl.com/libs/mixpanel-2-latest.min.js600.0 s31.7 KiB
cdn.peerj.com/cb040aa/webpack/1009.ce1d475f.js0.0 ms24.4 KiB
s3.amazonaws.com/static.peerj.com/images/journal-home/logos/logo-journal-cs.svg0.0 ms22.1 KiB
cdn.peerj.com/cb040aa/webpack/runtime.128817d8.js0.0 ms16.9 KiB
cdn.peerj.com/cb040aa/webpack/192.a4f13c83.js0.0 ms16.1 KiB
cdn.peerj.com/cb040aa/webpack/230.b4278b97.js0.0 ms9.3 KiB
cdn.peerj.com/cb040aa/webpack/253.a14f93c1.js0.0 ms7.8 KiB
cdn.peerj.com/cb040aa/webpack/198.0671974e.js0.0 ms7.4 KiB
cdn.peerj.com/cb040aa/webpack/66.1d672afc.js0.0 ms6.0 KiB
cdn.peerj.com/cb040aa/webpack/398.8481fb5e.js0.0 ms5.8 KiB
cdn.peerj.com/cb040aa/webpack/1021.178998b7.js0.0 ms5.2 KiB
cdn.peerj.com/cb040aa/webpack/1024.3817f300.js0.0 ms4.8 KiB
peerj.com/js/05779bd-a411a7a.js14400.0 s5.8 KiB
pushpad.xyz/pushpad.js14400.0 s5.7 KiB
cdn.peerj.com/cb040aa/webpack/0.447f5e85.js0.0 ms3.9 KiB
transcend-cdn.com/cm/ef49a3f1-d8c1-47d6-88fc-50e41130631f/tcf/tcf.css60.0 s3.4 KiB
cdn.peerj.com/cb040aa/webpack/1021.b4db90eb.css0.0 ms3.3 KiB
cdn.peerj.com/cb040aa/webpack/192.7954e175.css0.0 ms2.2 KiB
cdn.peerj.com/cb040aa/webpack/1042.5ccb8502.js0.0 ms2.2 KiB
cdn.peerj.com/cb040aa/webpack/1040.6aab3c12.js0.0 ms2.0 KiB
cdn.peerj.com/cb040aa/webpack/0.4a8639c8.css0.0 ms2.0 KiB
cdn.peerj.com/cb040aa/webpack/1009.ac3a2b66.css0.0 ms1.7 KiB
cdn.peerj.com/cb040aa/webpack/1024.3b00d89e.css0.0 ms1.0 KiB
peerj.com/assets/images/landing-pages/peerj-bio-logo.svg14400.0 s1.5 KiB
cdn.peerj.com/cb040aa/webpack/398.02ed4a60.css0.0 ms966 B
cdn.peerj.com/cb040aa/webpack/230.be4f9cb3.css0.0 ms896 B
peerj.com/assets/js/mixpanel.js14400.0 s1.0 KiB
cdn.peerj.com/cb040aa/webpack/66.58de92c7.css0.0 ms626 B
cdn.peerj.com/cb040aa/webpack/1042.678cac5e.css0.0 ms585 B
cdn.peerj.com/cb040aa/webpack/253.45f7f44a.css0.0 ms577 B
cdn.peerj.com/cb040aa/webpack/1040.251e73b2.css0.0 ms406 B
peerj.com/assets/js/polyfills/includes.js14400.0 s383 B
peerj.com/assets/js/polyfills/startsWith.js14400.0 s373 B

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:0.100626] map[node:map[boundingRect:map[bottom:3684 height:3684 left:0 right:1350 top:0 width:1350] lhId:page-1-BODY nodeLabel:body path:1,HTML,2,BODY selector:body snippet:<body class="" data-mp="776a79e14e8f05a81ca92536c83f08b4" data-mp-debug="" data-controllervars="" data-headervars="null" data-symfony-route="home" data-fixed-width="1440px"> type:node] score:0.059259] map[node:map[boundingRect:map[bottom:82 height:84 left:21 right:1329 top:-2 width:1308] lhId:page-7-DIV nodeLabel:PeerJ Submit Article Login path:1,HTML,2,BODY,1,DIV,0,DIV,0,DIV,0,DIV,2,DIV,0,HEADER,0,DIV,0,DIV,0,DIV selector:header.AppBar > div.v-toolbar__content > div.FixedWidthBody > div.FixedWidthBody-content snippet:<div data-v-67e31834="" class="FixedWidthBody-content" style="max-width: 1440px; width: 1308px; margin-left: 0px; margin-right: 0px;"> type:node] score:0.02798 subItems:map[items:[map[cause:Unsized image element extra:map[boundingRect:map[bottom:871 height:93 left:703 right:803 top:778 width:100] lhId:page-22-IMG nodeLabel:PeerJ Computer Science Icon path:1,HTML,2,BODY,1,DIV,0,DIV,0,DIV,0,DIV,4,MAIN,0,DIV,0,DIV,0,DIV,1,DIV,0,DIV,1,DIV,0,DIV,0,DIV,1,DIV,1,DIV,0,A,1,DIV,0,DIV,1,DIV,0,IMG selector:div.p-3 > div.d-flex > div > img snippet:<img data-v-f37613ea="" alt="PeerJ Computer Science Icon" src="https://s3.amazonaws.com/static.peerj.com/images/journal-home/logos/logo-j…" width="100" data-airgap-id="26"> type:node]]] type:subitems]] map[node:map[boundingRect:map[bottom:1093 height:531 left:20 right:1330 top:562 width:1310] lhId:page-4-DIV nodeLabel:Our Journals   PeerJ A multidisciplinary, open access journal publishing high-q… path:1,HTML,2,BODY,1,DIV,0,DIV,0,DIV,0,DIV,4,MAIN,0,DIV,0,DIV,0,DIV,1,DIV,0,DIV,1,DIV,0,DIV selector:div > div.SiteRoot > div.py-10 > div.FixedWidthBody-content snippet:<div data-v-1126372f="" class="FixedWidthBody-content" style="max-width: 1440px;"> type:node] score:0.007197 subItems:map[items:[map[cause:Unsized image element extra:map[boundingRect:map[bottom:871 height:93 left:36 right:136 top:778 width:100] lhId:page-21-IMG nodeLabel:PeerJ Icon path:1,HTML,2,BODY,1,DIV,0,DIV,0,DIV,0,DIV,4,MAIN,0,DIV,0,DIV,0,DIV,1,DIV,0,DIV,1,DIV,0,DIV,0,DIV,1,DIV,0,DIV,0,A,1,DIV,0,DIV,1,DIV,0,IMG selector:div.p-3 > div.d-flex > div > img snippet:<img data-v-f37613ea="" alt="PeerJ Icon" src="/assets/images/landing-pages/peerj-bio-logo.svg" width="100" data-airgap-id="25"> type:node]]] type:subitems]] map[node:map[boundingRect:map[bottom:985 height:96 left:703 right:1314 top:889 width:611] lhId:page-8-DIV nodeLabel:An open access journal advancing research in artificial intelligence, data scie… path:1,HTML,2,BODY,1,DIV,0,DIV,0,DIV,0,DIV,4,MAIN,0,DIV,0,DIV,0,DIV,1,DIV,0,DIV,1,DIV,0,DIV,0,DIV,1,DIV,1,DIV,0,A,1,DIV,1,DIV selector:div.col-md-6 > a.v-card > div.p-3 > div.mt-3 snippet:<div data-v-f37613ea="" class="mt-3 mb-4"> type:node] score:0.003116 subItems:map[items:[map[cause:Unsized image element extra:map[boundingRect:map[bottom:871 height:93 left:703 right:803 top:778 width:100] lhId:page-22-IMG nodeLabel:PeerJ Computer Science Icon path:1,HTML,2,BODY,1,DIV,0,DIV,0,DIV,0,DIV,4,MAIN,0,DIV,0,DIV,0,DIV,1,DIV,0,DIV,1,DIV,0,DIV,0,DIV,1,DIV,1,DIV,0,A,1,DIV,0,DIV,1,DIV,0,IMG selector:div.p-3 > div.d-flex > div > img snippet:<img data-v-f37613ea="" alt="PeerJ Computer Science Icon" src="https://s3.amazonaws.com/static.peerj.com/images/journal-home/logos/logo-j…" width="100" data-airgap-id="26"> type:node]]] type:subitems]] map[score:0.002875]]

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
cdn.peerj.com/cb040aa/webpack/fonts/materialdesignicons-webfont.bc2c1f6a.woff265 ms

A forced reflow occurs when JavaScript queries geometric properties (such as offsetWidth) after styles have been invalidated by a change to the DOM state. This can result in poor performance. Learn more about forced reflows and possible mitigations.

Why this matters

Performance issues directly impact user engagement and conversion rates.

headings: [map[key:source label:Source valueType:source-location] map[granularity:1 key:reflowTime label:Total reflow time valueType:ms]]
items: [map[reflowTime:26.732 source:map[column:34378 line:236 type:source-location url:https://cdn.peerj.com/cb040aa/webpack/peerj-app.6cc34b02.js urlProvider:network]] map[reflowTime:1.359 source:map[column:90389 line:265 type:source-location url:https://cdn.peerj.com/cb040aa/webpack/peerj-app.6cc34b02.js urlProvider:network]] map[reflowTime:6.557 source:map[column:49726 line:265 type:source-location url:https://cdn.peerj.com/cb040aa/webpack/peerj-app.6cc34b02.js urlProvider:network]]]

Optimize LCP by making the LCP image discoverable from the HTML immediately, and avoiding lazy-loading

Why this matters

Performance issues directly impact user engagement and conversion rates.

lhId: page-0-DIV
nodeLabel: div > div.HBanner > div.d-flex > div.HBanner-image
path: 1,HTML,2,BODY,1,DIV,0,DIV,0,DIV,0,DIV,4,MAIN,0,DIV,0,DIV,0,DIV,1,DIV,0,DIV,0,DIV,0,DIV,1,DIV,0,DIV
selector: div > div.HBanner > div.d-flex > div.HBanner-image
snippet: <div class="HBanner-image px-0 py-0">

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

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
cdn.peerj.com/cb040aa/webpack/peerj-app.6cc34b02.js623.1 KiB
cdn.peerj.com/cb040aa/webpack/330.a5145fec.js131.1 KiB168 ms
transcend-cdn.com/cm/ef49a3f1-d8c1-47d6-88fc-50e41130631f/airgap.js77.7 KiB445 ms
cdn.peerj.com/cb040aa/webpack/peerj-app.8ae05dc6.css79.3 KiB168 ms
cdn.peerj.com/cb040aa/webpack/runtime.128817d8.js16.9 KiB56 ms
cdn.peerj.com/cb040aa/webpack/330.3c2c95ca.css45.5 KiB363 ms
/css2?family=Inter:ital,opsz,wght@0,14..32,100..900;1,14....1.1 KiB281 ms
peerj.com/js/8d39319-582a9a0.js74.9 KiB168 ms
peerj.com/js/f67db00-8264f27.js93.4 KiB280 ms
peerj.com/js/05779bd-a411a7a.js5.8 KiB
peerj.com/assets/js/polyfills/startsWith.js373 B
peerj.com/assets/js/polyfills/includes.js383 B
cdn.peerj.com/cb040aa/webpack/198.0671974e.js7.4 KiB56 ms
peerj.com/css/01fda25-aa54668.css44.3 KiB112 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
div.col-md-6 > a.v-card > div.v-image > div.v-image__image div.col-md-6 > a.v-card > div.v-image > div.v-image__image
/images/journal-home/headers/PeerJ-Comp-Sci-Journal-Home-...446.0 KiB361.6 KiB
div.col-md-6 > a.v-card > div.v-image > div.v-image__image div.col-md-6 > a.v-card > div.v-image > div.v-image__image
/images/journal-home/headers/PeerJ-Journal-Home-950w.jpg380.9 KiB305.9 KiB

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
body body
0.059
PeerJ Submit Article Login header.AppBar > div.v-toolbar__content > div.FixedWidthBody > div.FixedWidthBody-content
0.028
Our Journals   PeerJ A multidisciplinary, open access journal publishing high-q… div > div.SiteRoot > div.py-10 > div.FixedWidthBody-content
0.007
An open access journal advancing research in artificial intelligence, data scie… div.col-md-6 > a.v-card > div.p-3 > div.mt-3
0.003
0.003
Explore Journal div.col-md-6 > a.v-card > div.p-3 > div.d-flex
0.000

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

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

Minifying JavaScript files can reduce payload sizes and script parse time. Learn how to minify JavaScript.

Why this matters

Performance issues directly impact user engagement and conversion rates.

Estimated savings: 170 ms 80.2 KiB
URLTransfer SizeEst Savings
peerj.com/js/f67db00-8264f27.js93.3 KiB44.6 KiB
peerj.com/js/8d39319-582a9a0.js74.8 KiB33.3 KiB
peerj.com/js/05779bd-a411a7a.js5.6 KiB2.3 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: 190 ms 175.1 KiB
URLTransfer SizeEst Savings
cdn.peerj.com/cb040aa/webpack/peerj-app.8ae05dc6.css79.0 KiB77.7 KiB
peerj.com/css/01fda25-aa54668.css44.0 KiB43.6 KiB
cdn.peerj.com/cb040aa/webpack/330.3c2c95ca.css45.2 KiB42.3 KiB
:root { --v-anchor-base: #10147e; --v-primary-base: #10147e; --v-primary-lighten5: #ab8cff; …13.1 KiB11.5 KiB

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: 560 ms 683.3 KiB
URLTransfer SizeEst Savings
cdn.peerj.com/cb040aa/webpack/peerj-app.6cc34b02.js612.8 KiB468.4 KiB
cdn.peerj.com/cb040aa/webpack/330.a5145fec.js130.8 KiB64.4 KiB
peerj.com/js/8d39319-582a9a0.js74.8 KiB50.4 KiB
peerj.com/js/f67db00-8264f27.js93.3 KiB45.6 KiB
transcend-cdn.com/cm/ef49a3f1-d8c1-47d6-88fc-50e41130631f/tcf/ui.js84.4 KiB28.5 KiB
cdn.mxpnl.com/libs/mixpanel-2-latest.min.js31.2 KiB26.0 KiB

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: 0.0 ms 9.3 KiB
URLTransfer SizeEst Savings
peerj.com/css/01fda25-aa54668.css44.3 KiB9.3 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
cdn.peerj.com/cb040aa/webpack/peerj-app.6cc34b02.js623.1 KiB
/images/journal-home/headers/PeerJ-Comp-Sci-Journal-Home-...446.6 KiB
/images/journal-home/headers/PeerJ-Journal-Home-950w.jpg381.5 KiB
cdn.peerj.com/cb040aa/webpack/fonts/materialdesignicons-webfont.bc2c1f6a.woff2284.2 KiB
d2pdyyx74uypu5.cloudfront.net/images/home/PeerJHomepageSplash-1908x450.jpg139.5 KiB
cdn.peerj.com/cb040aa/webpack/330.a5145fec.js131.1 KiB
peerj.com/js/f67db00-8264f27.js93.4 KiB
transcend-cdn.com/cm/ef49a3f1-d8c1-47d6-88fc-50e41130631f/tcf/ui.js84.7 KiB
cdn.peerj.com/cb040aa/webpack/peerj-app.8ae05dc6.css79.3 KiB
fonts.gstatic.com/s/inter/v20/UcCm3FwrK3iLTcvnUwQT9mI1F54.woff277.9 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
PeerJ Icon div.p-3 > div.d-flex > div > img
peerj.com/assets/images/landing-pages/peerj-bio-logo.svg
PeerJ Computer Science Icon div.p-3 > div.d-flex > div > img
s3.amazonaws.com/static.peerj.com/images/journal-home/logos/logo-journal-cs.svg

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

●Document request latency
●Optimize DOM size
●LCP breakdown
●Modern HTTP
●Optimize viewport for mobile
●JavaScript execution time 0.6 s
●Minimizes main-thread work 1.0 s
●Avoid long main-thread tasks 2 long tasks found
●Avoid non-composited animations 6 animated elements found
●Page didn't prevent back/forward cache restoration
●Network Requests
●Network Round Trip Times 100 ms
●Server Backend Latencies 30 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 440 ms
○INP breakdown
○User Timing marks and measures
100

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.

○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
●Buttons have an accessible name
●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
●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 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
●No element has a `[tabindex]` value greater than 0
●Touch targets have sufficient size and spacing.
●Heading elements appear in a sequentially-descending order
●Document has a main landmark.
●Deprecated ARIA roles were not used
●Identical links have the same purpose.
●Elements with visible text labels have matching accessible names.
○`[accesskey]` values are unique
○`button`, `link`, and `menuitem` elements have accessible names
○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
○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
○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
○Links are distinguishable without relying on color.
○The document does not use `<meta http-equiv="refresh">`
○`<object>` elements have alternate text
○Select elements have associated label elements.
○Skip links are focusable.
○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
○Image elements do not have `[alt]` attributes that are redundant text.
○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.
96

Best Practices

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.

SourceDescription
transcend-cdn.com/cm/ef49a3f1-d8c1-47d6-88fc-50e41130631f/airgap.js line 10, col 1404
Error: <svg> attribute width: Expected length, "width".

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
cdn.peerj.com/cb040aa/webpack/peerj-app.6cc34b02.js
●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 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
○Redirects HTTP traffic to HTTPS
○Mitigate clickjacking with XFO or CSP
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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