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
search.worldcat.org/inter/Inter-Bold.woff2?v=3.19	7200.0 s	104.0 KiB
search.worldcat.org/inter/Inter-Medium.woff2?v=3.19	7200.0 s	103.8 KiB
search.worldcat.org/inter/Inter-SemiBold.woff2?v=3.19	7200.0 s	103.7 KiB
search.worldcat.org/inter/Inter-Regular.woff2?v=3.19	7200.0 s	97.0 KiB
cdn.cookielaw.org/scripttemplates/202503.1.0/otBannerSdk.js	86400.0 s	115.9 KiB
/cdn-cgi/challenge-platform/h/b/scripts/jsd/0b8fb825cb67/...	14400.0 s	11.2 KiB
/ImageWebSvc/oclc/+-+81733128_140.jpg?allowDefault=false&...	478702.0 s	42.8 KiB
/logos/ae95f2c4-d4f7-4b4f-a299-1dd96c032e18/3c1fd33b-6c13...	86400.0 s	11.8 KiB
/ImageWebSvc/oclc/+-+27234939_140.jpg?allowDefault=false&...	478702.0 s	34.0 KiB
/ImageWebSvc/oclc/+-+25157410_140.jpg?allowDefault=false&...	478702.0 s	32.9 KiB
cdn.cookielaw.org/scripttemplates/otSDKStub.js	86400.0 s	9.1 KiB
/beacon.min.js/vcd15cbe7772f49c399c6a5babf22c124171768917...	86400.0 s	6.9 KiB
cdn.cookielaw.org/consent/3b9b6a99-a8b7-4b31-a427-748bf51c2056/OtAutoBlock.js	86400.0 s	4.5 KiB
/ImageWebSvc/oclc/+-+88607862_140.jpg?allowDefault=false&...	478702.0 s	11.1 KiB
cdn.cookielaw.org/logos/static/powered_by_logo.svg	86400.0 s	2.6 KiB
search.worldcat.org/inter.css	7200.0 s	1.3 KiB
search.worldcat.org/survey-monkey.css	7200.0 s	1.0 KiB

Your first network request is the most important. Reduce its latency by avoiding redirects, ensuring a fast server response, and enabling text compression.

Why this matters

Performance issues directly impact user engagement and conversion rates.

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:42.301 source:map[type:text value:[unattributed]]]]

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:406.4979990234375 label:Time to first byte subpart:timeToFirstByte] map[duration:1290.9400009765625 label:Resource load delay subpart:resourceLoadDelay] map[duration:109.13 label:Resource load duration subpart:resourceLoadDuration] map[duration:788.079 label:Element render delay subpart:elementRenderDelay]]

lhId: page-0-IMG

nodeLabel: mobile website view of searchworldcat.org.

path: 1,HTML,1,BODY,2,DIV,2,MAIN,1,DIV,0,DIV,0,DIV,1,DIV,0,DIV,0,DIV,2,PICTURE,2,IMG

selector: div.tss-1x0fvju-imageContainer > div.tss-170vpu5-img > picture > img

snippet: <img alt="mobile website view of searchworldcat.org." src="https://www.datocms-assets.com/29926/1747055897-217606_worldcatorg_homepag…" style="opacity: 1; transition: opacity 500ms; position: absolute; left: 0px;">

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-IMG

nodeLabel: mobile website view of searchworldcat.org.

path: 1,HTML,1,BODY,2,DIV,2,MAIN,1,DIV,0,DIV,0,DIV,1,DIV,0,DIV,0,DIV,2,PICTURE,2,IMG

selector: div.tss-1x0fvju-imageContainer > div.tss-170vpu5-img > picture > img

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

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	Duration
search.worldcat.org/survey-monkey.css	1.0 KiB
search.worldcat.org/inter.css	1.3 KiB
cdn.cookielaw.org/consent/3b9b6a99-a8b7-4b31-a427-748bf51c2056/OtAutoBlock.js	4.5 KiB	808 ms
cdn.cookielaw.org/scripttemplates/otSDKStub.js	9.1 KiB	167 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.

	URL	Resource Size	Est Savings
Front cover image for Carrots love tomatoes : secrets of companion planting for… `a.MuiTypography-root > span.MuiBox-root > div.MuiBox-root > img.tss-r9zhz7-coverOriginal`	/ImageWebSvc/oclc/+-+81733128_140.jpg?allowDefault=false&...	42.5 KiB	39.3 KiB
Front cover image for Cubed foot gardening : growing vegetables in raised inten… `a.MuiTypography-root > span.MuiBox-root > div.MuiBox-root > img.tss-r9zhz7-coverOriginal`	/ImageWebSvc/oclc/+-+27234939_140.jpg?allowDefault=false&...	33.7 KiB	30.5 KiB
Front cover image for Native plants for prairie gardens `a.MuiTypography-root > span.MuiBox-root > div.MuiBox-root > img.tss-r9zhz7-coverOriginal`	/ImageWebSvc/oclc/+-+25157410_140.jpg?allowDefault=false&...	32.6 KiB	29.5 KiB
mobile website view of searchworldcat.org. `div.tss-1x0fvju-imageContainer > div.tss-170vpu5-img > picture > img`	/29926/1747055897-217606_worldcatorg_homepageimage_622x34...	32.9 KiB	21.3 KiB
Front cover image for Native alternatives to invasive plants `a.MuiTypography-root > span.MuiBox-root > div.MuiBox-root > img.tss-r9zhz7-coverOriginal`	/ImageWebSvc/oclc/+-+88607862_140.jpg?allowDefault=false&...	10.9 KiB	7.7 KiB

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: 916 ms

URL	Time Spent
worldcat.org/	916 ms
search.worldcat.org/	0.0 ms

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.

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

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: 3.2 s 1.2 MiB

URL	Transfer Size	Est Savings
search.worldcat.org/_next/static/chunks/81-9089fe14406a16cb.js	556.8 KiB	388.7 KiB
search.worldcat.org/_next/static/chunks/58474bfb-5251dc1630dc5126.js	317.8 KiB	224.8 KiB
search.worldcat.org/_next/static/chunks/pages/_app-179c87dcd1fa8d64.js	327.8 KiB	103.7 KiB
search.worldcat.org/_next/static/chunks/1d2671aa-f600276eb687cd2d.js	192.7 KiB	97.9 KiB
cdn.cookielaw.org/scripttemplates/202503.1.0/otBannerSdk.js	115.8 KiB	64.4 KiB
cdn.cookielaw.org/scripttemplates/202503.1.0/otBannerSdk.js	115.8 KiB	63.8 KiB
www.googletagmanager.com/gtm.js?id=GTM-T78H6Q6	141.2 KiB	55.2 KiB
/_next/static/chunks/pages/lists/[listId]-0b27c484aa752a8...	53.1 KiB	51.4 KiB
search.worldcat.org/_next/static/chunks/4163-dd9706b6c3d6413d.js	77.8 KiB	40.5 KiB
search.worldcat.org/_next/static/chunks/5384-aa942c8f13d5d03d.js	48.6 KiB	38.0 KiB
search.worldcat.org/_next/static/chunks/5572-ae03a66fd13bfa0e.js	34.1 KiB	32.7 KiB
search.worldcat.org/_next/static/chunks/381-4f05c7cf29185b87.js	29.6 KiB	28.2 KiB
search.worldcat.org/_next/static/chunks/6386-14ce1e0b0c2ee544.js	27.2 KiB	26.1 KiB
search.worldcat.org/_next/static/chunks/1583-af5ed127e6a143e7.js	26.9 KiB	25.1 KiB
search.worldcat.org/_next/static/chunks/framework-378c8f1031e2e5b2.js	58.6 KiB	20.6 KiB

Consider reducing the time spent parsing, compiling, and executing JS. You may find delivering smaller JS payloads helps with this. Learn how to reduce Javascript execution time.

Why this matters

Performance issues directly impact user engagement and conversion rates.

URL	Total CPU Time	Script Evaluation	Script Parse
search.worldcat.org/_next/static/chunks/framework-378c8f1031e2e5b2.js	2.2 s	2.1 s	28 ms
search.worldcat.org/	916 ms	346 ms	22 ms
Unattributable	623 ms	85 ms	0.0 ms
cdn.cookielaw.org/scripttemplates/202503.1.0/otBannerSdk.js	568 ms	362 ms	125 ms
www.googletagmanager.com/gtm.js?id=GTM-T78H6Q6	438 ms	366 ms	42 ms
search.worldcat.org/_next/static/chunks/pages/_app-179c87dcd1fa8d64.js	434 ms	311 ms	122 ms
search.worldcat.org/_next/static/chunks/81-9089fe14406a16cb.js	393 ms	348 ms	40 ms
search.worldcat.org/_next/static/chunks/2391.aede3f03048b823f.js	332 ms	315 ms	6.2 ms
search.worldcat.org/_next/static/chunks/main-ac5ca2eebc7ba9d0.js	255 ms	208 ms	12 ms
search.worldcat.org/cdn-cgi/challenge-platform/scripts/jsd/main.js	252 ms	241 ms	2.0 ms
search.worldcat.org/_next/static/chunks/4611.54b96443e1087e33.js	139 ms	88 ms	0.6 ms
js-agent.newrelic.com/nr-spa-1.266.0.min.js	138 ms	116 ms	8.9 ms
search.worldcat.org/_next/static/chunks/pages/index-6c78cc84a2744c79.js	113 ms	109 ms	2.4 ms
cdn.cookielaw.org/scripttemplates/otSDKStub.js	72 ms	42 ms	6.9 ms
/beacon.min.js/vcd15cbe7772f49c399c6a5babf22c124171768917...	54 ms	32 ms	1.4 ms

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.

Category	Time Spent
Script Evaluation	5.1 s
Other	839 ms
Script Parsing & Compilation	542 ms
Style & Layout	381 ms
Parse HTML & CSS	117 ms
Garbage Collection	100 ms
Rendering	59 ms

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: 0.0 ms 19.0 KiB

URL	Transfer Size	Est Savings
	21.8 KiB	19.0 KiB

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

●Layout shift culprits

●Optimize DOM size

●Font display

●Modern HTTP

●Optimize viewport for mobile

●Minify CSS

●Minify JavaScript

●Avoids enormous network payloads Total size was 2,248 KiB

●User Timing marks and measures 7 user timings

●Avoid long main-thread tasks 20 long tasks found

●Avoid non-composited animations 1 animated element found

●Image elements have explicit `width` and `height`

●Page didn't prevent back/forward cache restoration

●Network Requests

●Network Round Trip Times 120 ms

●Server Backend Latencies 290 ms

●Tasks

●Diagnostics

●Metrics

●Screenshot Thumbnails

●Final Screenshot

●Script Treemap Data

●Resources Summary

●Initial server response time was short Root document took 220 ms

○INP breakdown

○Avoid large layout shifts

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.

Visible text labels that do not match the accessible name can result in a confusing experience for screen reader users. Learn more about accessible names.

Why this matters

Performance issues directly impact user engagement and conversion rates.

Failing Elements
France `header.tss-1qnrdk0-root > nav.tss-1qng7v4-flex-nav > div.MuiBox-root > button#location-confirmer-desktop`
Learn more `div.tss-eut5c9-interestsRow > div.tss-1jpfdrg-centered-interestsGrid > div.tss-19qhrot-truncate > a.MuiButtonBase-root`
Learn more `div.tss-eut5c9-interestsRow > div.tss-1jpfdrg-centered-interestsGrid > div.tss-19qhrot-truncate > a.MuiButtonBase-root`
Learn more `div.tss-eut5c9-interestsRow > div.tss-1jpfdrg-centered-interestsGrid > div.tss-19qhrot-truncate > a.MuiButtonBase-root`
Native plants for prairie gardens `div.MuiBox-root > div.tss-1ttzg4z-grid-carouselHeight-active > div.tss-xm45v6-root > a.MuiTypography-root`
Carrots love tomatoes : secrets of companion planting for successful gardening `div.MuiBox-root > div.tss-1ttzg4z-grid-carouselHeight-active > div.tss-xm45v6-root > a.MuiTypography-root`
Cubed foot gardening : growing vegetables in raised intensive beds `div.MuiBox-root > div.tss-1ttzg4z-grid-carouselHeight-active > div.tss-xm45v6-root > a.MuiTypography-root`
Native alternatives to invasive plants `div.MuiBox-root > div.tss-1ttzg4z-grid-carouselHeight-active > div.tss-xm45v6-root > a.MuiTypography-root`
Learn more `div.tss-159q7d1-row-howToUseRow > div.tss-m3jeqp-centered-howToUseGrid > div.tss-xee8kb-root > a.MuiTypography-root`
Learn more `div.tss-159q7d1-row-howToUseRow > div.tss-m3jeqp-centered-howToUseGrid > div.tss-xee8kb-root > a.MuiTypography-root`
Learn more `div.tss-wzue4g-root > div.tss-1y4gm05-row-centered-largeGraphicRow > div.MuiBox-root > a.MuiTypography-root`
Eco-literacy for kids The more kids understand about how the natural world wor… `div.MuiBox-root > div.MuiBox-root > div.tss-1ttzg4z-grid-carouselHeight-active > a.tss-bv52uj-cardLink`
Nature Documentaries From snow-capped mountains to wildlife thriving in the co… `div.MuiBox-root > div.MuiBox-root > div.tss-1ttzg4z-grid-carouselHeight-active > a.tss-bv52uj-cardLink`
Top interlibrary loan requests: March 2026 Here are the ten books most frequen… `div.MuiBox-root > div.MuiBox-root > div.tss-1ttzg4z-grid-carouselHeight-active > a.tss-bv52uj-cardLink`

○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

●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.

●Select elements have associated label elements.

●ARIA attributes are used as specified for the element's role

●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

●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

●No element has a `[tabindex]` value greater than 0

●Touch targets have sufficient size and spacing.

●`[lang]` attributes have a valid value

●Heading elements appear in a sequentially-descending order

●Document has a main landmark.

●Deprecated ARIA roles were not used

●ARIA IDs are unique

○`[accesskey]` values are unique

○`button`, `link`, and `menuitem` elements 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

○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

○Links are distinguishable without relying on color.

○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">`

○`<object>` elements have alternate text

○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.

○`<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.

○Identical links have the same purpose.

○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.

Best Practices

User Experience

Image display dimensions should match natural aspect ratio. Learn more about image aspect ratio.

Why this matters

Performance issues directly impact user engagement and conversion rates.

	Aspect Ratio (Displayed)	Aspect Ratio (Actual)
div.tss-19qhrot-truncate > div.tss-1x0fvju-imageContainer > div.tss-170vpu5-img > img `div.tss-19qhrot-truncate > div.tss-1x0fvju-imageContainer > div.tss-170vpu5-img > img`	392 x 219 (1.79)	24 x 14 (1.71)
div.tss-19qhrot-truncate > div.tss-1x0fvju-imageContainer > div.tss-170vpu5-img > img `div.tss-19qhrot-truncate > div.tss-1x0fvju-imageContainer > div.tss-170vpu5-img > img`	392 x 219 (1.79)	24 x 14 (1.71)
div.tss-19qhrot-truncate > div.tss-1x0fvju-imageContainer > div.tss-170vpu5-img > img `div.tss-19qhrot-truncate > div.tss-1x0fvju-imageContainer > div.tss-170vpu5-img > img`	392 x 219 (1.79)	24 x 14 (1.71)
div.MuiPaper-root > div.tss-ryvsv2-img > div > img `div.MuiPaper-root > div.tss-ryvsv2-img > div > img`	310 x 174 (1.78)	24 x 14 (1.71)
div.MuiPaper-root > div.tss-ryvsv2-img > div > img `div.MuiPaper-root > div.tss-ryvsv2-img > div > img`	310 x 174 (1.78)	24 x 14 (1.71)
div.MuiPaper-root > div.tss-ryvsv2-img > div > img `div.MuiPaper-root > div.tss-ryvsv2-img > div > img`	310 x 174 (1.78)	24 x 14 (1.71)

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
div.tss-19qhrot-truncate > div.tss-1x0fvju-imageContainer > div.tss-170vpu5-img > img `div.tss-19qhrot-truncate > div.tss-1x0fvju-imageContainer > div.tss-170vpu5-img > img`		392 x 219	24 x 14	588 x 329

General

Deprecated APIs will eventually be removed from the browser. Learn more about deprecated APIs.

Why this matters

Performance issues directly impact user engagement and conversion rates.

Deprecation / Warning	Source
SharedStorage	search.worldcat.org/cdn-cgi/challenge-platform/scripts/jsd/main.js
StorageType.persistent is deprecated. Please use standardized navigator.storage instead.	search.worldcat.org/cdn-cgi/challenge-platform/scripts/jsd/main.js
Fledge	search.worldcat.org/cdn-cgi/challenge-platform/scripts/jsd/main.js

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
/_next/image?url=https%3A%2F%2Fwww.datocms-assets.com%2F2...	`Failed to load resource: the server responded with a status of 400 ()`
/_next/image?url=https%3A%2F%2Fwww.datocms-assets.com%2F2...	`Failed to load resource: the server responded with a status of 400 ()`
/_next/image?url=https%3A%2F%2Fwww.datocms-assets.com%2F2...	`Failed to load resource: the server responded with a status of 400 ()`

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
search.worldcat.org/_next/static/chunks/pages/_app-179c87dcd1fa8d64.js
search.worldcat.org/_next/static/chunks/81-9089fe14406a16cb.js

●Uses HTTPS

●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

●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 clickjacking with XFO or CSP

●Mitigate DOM-based XSS with Trusted Types

●Detected JavaScript libraries

○Redirects HTTP traffic to HTTPS

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

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
/lists/3ba1e03f-24dc-4ee2-8c76-44b063acc6fe?limit=25&offs...	Learn more
search.worldcat.org/create-account	Learn more
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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

●Document has a meta description

●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`