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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.

36

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.

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.

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.

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
Homepage Banner Slide 2 div.min-w-0 > a.block > picture > img.h-auto
/bkshp-prod-content-images/homepage_banner_slides/aa6559a...236.1 KiB205.6 KiB
Homepage Banner Slide 1 div.min-w-0 > a.block > picture > img.h-auto
/bkshp-prod-content-images/homepage_banner_slides/677194a...213.7 KiB183.1 KiB
Homepage Banner Slide 3 div.min-w-0 > a.block > picture > img.h-auto
/bkshp-prod-content-images/homepage_banner_slides/53afc81...204.6 KiB174.0 KiB
Thirty-Two Words for Field bookcover div.flex > div.flex > a.relative > img.shadow-[0px
/ingram/9781645023760.jpg?v=40c5bc4baea625b61045a62e4d6eb...72.7 KiB62.8 KiB
Break Room div.w-2/5 > div.flex > div.text-center > img.mb-2
/ingram/9781639739073.jpg?v=6ed3229df8e118060ad3f7d0d91c472359.4 KiB56.7 KiB
The Fifth Season bookcover div.flex > div.flex > a.relative > img.shadow-[0px
/ingram/9780316229296.jpg?v=64206704e30e1f68382a16806300b...64.0 KiB53.8 KiB
The Overstory bookcover div.flex > div.flex > a.relative > img.shadow-[0px
/ingram/9780393356687.jpg?v=ecdb23567e120999dad2f6632e965...60.5 KiB50.2 KiB
Man's Search for Meaning bookcover div.flex > div.flex > a.relative > img.shadow-[0px
images-us.bookshop.org/ingram/9780807014271.jpg?v=enc-v1&height=50058.5 KiB48.6 KiB
Concrete Botany bookcover div.flex > div.flex > a.relative > img.shadow-[0px
/ingram/9780760391884.jpg?v=8eae4fefe75f1ddb5ff69afecff91...56.8 KiB44.2 KiB
Helm bookcover div.flex > div.flex > a.relative > img.shadow-[0px
/ingram/9780063439948.jpg?v=68844af70a99cd3cb353d930a079f...52.4 KiB42.3 KiB
Guinness World Records 2026 bookcover div.flex > div.flex > a.relative > img.shadow-[0px
/ingram/9781913484750.jpg?v=3881fa865d60cda1085fdee7db838...46.2 KiB34.6 KiB
I'm Just a Little Guy bookcover div.flex > div.flex > a.relative > img.shadow-[0px
/ingram/9781683694946.jpg?v=6238ef6f28ae5f9d1e349c59b8f8a...44.1 KiB31.2 KiB
Annihilation bookcover div.flex > div.flex > a.relative > img.shadow-[0px
/ingram/9781250824042.jpg?v=0723de7ffecdc86779a360584da14...40.7 KiB30.4 KiB
The Wretched of the Earth bookcover div.flex > div.flex > a.relative > img.shadow-[0px
/ingram/9780802158635.jpg?v=d331a6efc64e2c257ce9e38ec01bc...37.4 KiB27.5 KiB
How High We Go in the Dark bookcover div.flex > div.flex > a.relative > img.shadow-[0px
/ingram/9780063072657.jpg?v=cb6b65e2aa31036ebebc2a30182d0...36.0 KiB25.8 KiB
Metropolitans bookcover div.flex > div.flex > a.relative > img.shadow-[0px
/ingram/9781662603006.jpg?v=ef76f2eed9b6d6a937aa6cf3f25ee...36.1 KiB25.8 KiB
The Seed Keeper bookcover div.flex > div.flex > a.relative > img.shadow-[0px
/ingram/9781571311375.jpg?v=c62634654331472e362ee41f1f2b4...34.8 KiB24.8 KiB
Orbital bookcover div.flex > div.flex > a.relative > img.shadow-[0px
/ingram/9780802163622.jpg?v=b1e38abc6d9229a5924ba4e0e3bd0...34.7 KiB24.0 KiB
Endling bookcover div.flex > div.flex > a.relative > img.shadow-[0px
/ingram/9780385545310.jpg?v=13ee7330dd1479492913f4f3b1b27...33.6 KiB23.4 KiB
Field Notes from an Extinction bookcover div.flex > div.flex > a.relative > img.shadow-[0px
/ingram/9781644215340.jpg?v=4e68e0d5c24e3fcdb73e48799f447...33.7 KiB23.4 KiB
Fever Dream bookcover div.flex > div.flex > a.relative > img.shadow-[0px
/ingram/9780399184604.jpg?v=ca41ee376e9a92234cb6d0e25b6f7...33.8 KiB22.8 KiB
Mutual Aid bookcover div.flex > div.flex > a.relative > img.shadow-[0px
/ingram/9781836742555.jpg?v=893084c7b87a418f69159084428d5...32.4 KiB22.8 KiB
bookcover for Last Night in Brooklyn section.my-[24px] > a.flex > div.relative > img.rounded-[3px]
/ingram/9781250372031.jpg?v=df1edc5c4f07c64aaadd208d43d0a...34.0 KiB21.9 KiB
A Philosophy of Walking bookcover div.flex > div.flex > a.relative > img.shadow-[0px
/ingram/9781804290446.jpg?v=2989dea091844e0483f1e513a6843...31.8 KiB21.7 KiB
Forest Euphoria bookcover div.flex > div.flex > a.relative > img.shadow-[0px
/ingram/9781954118904.jpg?v=623cfbfe2b5b260a2e7062d349e1b...32.0 KiB21.7 KiB
Wild Dark Shore bookcover div.flex > div.flex > a.relative > img.shadow-[0px
/ingram/9781250827951.jpg?v=eaf4d0e5322b82e0cfb66ed4b5cd6...31.8 KiB21.7 KiB
The Ministry of Time bookcover div.flex > div.flex > a.relative > img.shadow-[0px
/ingram/9781668045152.jpg?v=3ac523cb1a0cebd309adf2959f7f5...31.7 KiB21.6 KiB
Democracy Awakening bookcover section.my-[24px] > a.flex > div.relative > img.shadow-[0px
/ingram/9780593652978.jpg?v=f4b235a1c49591f99fb70e442cf2f...33.5 KiB21.5 KiB
The Gales of November bookcover div.flex > div.flex > a.relative > img.shadow-[0px
/ingram/9781324094647.jpg?v=68d064d551e3ad8b0465d24a1583f...30.5 KiB20.5 KiB
bookcover for The Language of Liars section.my-[24px] > a.flex > div.relative > img.rounded-[3px]
/ingram/9781250405333.jpg?v=3ab62d26b359c743f3cb7980e13cb...31.6 KiB20.1 KiB
Once There Were Wolves bookcover div.flex > div.flex > a.relative > img.shadow-[0px
/ingram/9781250244154.jpg?v=9d62253573549c5396e32844b583f...28.7 KiB18.7 KiB
Parable of the Sower bookcover div.flex > div.flex > a.relative > img.shadow-[0px
/ingram/9781538732182.jpg?v=3e5387557d5bedf789876fbb46f42...27.4 KiB17.3 KiB
bookcover for This Vast Enterprise section.my-[24px] > a.flex > div.relative > img.rounded-[3px]
/ingram/9781982174248.jpg?v=e81b7dd1889ca32cd6c13f38bfea0...29.2 KiB17.1 KiB
The Secret Life of a Cemetery bookcover div.flex > div.flex > a.relative > img.shadow-[0px
/ingram/9781778403903.jpg?v=766a28bd1db43d54793253eb0e1f4...25.8 KiB16.0 KiB
A Guardian and a Thief: Oprah's Book Club bookcover div.flex > div.flex > a.relative > img.shadow-[0px
/ingram/9780593804872.jpg?v=4ebd467f1677809f0c9b34b343ae1...24.0 KiB14.9 KiB
bookcover for I'll Believe in Anything section.my-[24px] > a.flex > div.relative > img.rounded-[3px]
/ingram/9780316613941.jpg?v=86a2248350606e2500b2262a430d1...27.0 KiB14.8 KiB
Vigil bookcover div.flex > div.flex > a.relative > img.shadow-[0px
/ingram/9780525509622.jpg?v=7c0f3c4f862ceb10cda8127d76b26...23.8 KiB14.8 KiB
The Glorians bookcover div.flex > div.flex > a.relative > img.shadow-[0px
/ingram/9780802165848.jpg?v=f5edaac18239abcfe8c3082d7907f...21.4 KiB13.3 KiB
Go Gentle: Oprah's Book Club div.w-2/5 > div.flex > div.text-center > img.mb-2
/ingram/9798217176632.jpg?v=335365088c4b4508186fd7c7c988066019.4 KiB13.2 KiB
On Democracy bookcover div.flex > div.flex > a.relative > img.shadow-[0px
/ingram/9781598538465.jpg?v=a4f307563128d0f74879bd3054dce...20.0 KiB12.4 KiB
bookcover for Yesteryear: A GMA Book Club Pick section.my-[24px] > a.flex > div.relative > img.rounded-[3px]
/ingram/9780593804216.jpg?v=dfc2aea20951d9bf99b213c90ac32...22.3 KiB12.3 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:372.558 label:Time to first byte subpart:timeToFirstByte] map[duration:21.408 label:Resource load delay subpart:resourceLoadDelay] map[duration:698.496 label:Resource load duration subpart:resourceLoadDuration] map[duration:1447.624 label:Element render delay subpart:elementRenderDelay]]
lhId: page-1-IMG
nodeLabel: Homepage Banner Slide 1
path: 1,HTML,1,BODY,41,DIV,2,DIV,0,DIV,0,DIV,0,DIV,0,A,0,PICTURE,2,IMG
selector: div.min-w-0 > a.block > picture > img.h-auto
snippet: <img alt="Homepage Banner Slide 1" fetchpriority="high" loading="eager" width="2048" height="600" decoding="async" data-nimg="1" class="h-auto w-full" srcset="/_next/image?url=https%3A%2F%2Fstorage.googleapis.com%2Fbkshp-prod-content…" src="https://storage.googleapis.com/bkshp-prod-content-images/homepage_banner_s…" style="color: transparent;">

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.

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

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

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: 832 ms
URLTime Spent
bookshop.org/832 ms
bookshop.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.

Diagnostics

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 13.2 KiB
URLTransfer SizeEst Savings
bookshop.org/_next/static/css/9565bed5101f4c37.css16.3 KiB13.2 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.

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.

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
Script Evaluation2.7 s
Other1.4 s
Script Parsing & Compilation462 ms
Style & Layout263 ms
Parse HTML & CSS101 ms
Rendering94 ms
Garbage Collection86 ms

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 reasonFailure type
Pages with cache-control:no-store header cannot enter back/forward cache.Actionable
Pages whose main resource has cache-control:no-store cannot enter back/forward cache.Not actionable
Back/forward cache is disabled because some JavaScript network request received resource with Cache-Control: no-store header.Not actionable

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

Layout shift culprits
Optimize DOM size
Forced reflow
LCP request discovery
Modern HTTP
Optimize viewport for mobile
Minify CSS
Minify JavaScript
User Timing marks and measures 8 user timings
Avoid long main-thread tasks 19 long tasks found
Avoid non-composited animations 2 animated elements found
Image elements have explicit `width` and `height`
Network Requests
Network Round Trip Times 100 ms
Server Backend Latencies 500 ms
Tasks
Diagnostics
Metrics
Screenshot Thumbnails
Final Screenshot
Script Treemap Data
Resources Summary
Initial server response time was short Root document took 300 ms
Avoid large layout shifts 1 layout shift found
INP breakdown
92

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

Informative elements should aim for short, descriptive alternate text. Decorative elements can be ignored with an empty alt attribute. Learn more about the `alt` attribute.

Why this matters

Performance issues directly impact user engagement and conversion rates.

Failing Elements
body > img body > img

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
Go to slide 1 div.w-full > div.flex > div.flex > button.h-[10px]
Go to slide 2 div.w-full > div.flex > div.flex > button.h-[10px]
Go to slide 3 div.w-full > div.flex > div.flex > button.h-[10px]

These items highlight common accessibility best practices.

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
Bookshop.org div.col-span-1 > section.my-[24px] > div.order-[-1] > a
Bookshop.org div.col-span-1 > section.my-[24px] > div.order-[-1] > a
LEARN MORE div.flex > div.mt-auto > a.block > button.tag-label
LEARN MORE div.flex > div.mt-auto > a.block > button.tag-label
Bookshop.org div.col-span-1 > div.flex > div.flex > a
View All (50) div.col-span-1 > div.flex > div.flex > a
Independent Publishers Caucus div.col-span-1 > div.flex > div.flex > a
View All (40) div.col-span-1 > div.flex > div.flex > a
US/EN div.flex > section.w-full > div.flex > a.flex
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
Elements with an ARIA `[role]` that require children to contain a specific `[role]` have all required children.
`[role]` values are valid
`[aria-*]` attributes have valid values
`[aria-*]` attributes are valid and not misspelled
Buttons have an accessible name
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 with `role="dialog"` or `role="alertdialog"` have accessible names.
`[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
`<frame>` or `<iframe>` elements have a title
`<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
No element has a `[tabindex]` value greater than 0
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.
`[accesskey]` values are unique
`button`, `link`, and `menuitem` elements have accessible names
ARIA input fields have accessible names
ARIA `meter` elements have accessible names
ARIA `progressbar` elements have accessible names
`[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
`<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.
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.
92

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.

URLAspect Ratio (Displayed)Aspect Ratio (Actual)
undefined div.flex > div.flex > a > img.border-gray
/spree/affiliate_profiles/profile_images/13429/original/I...40 x 40 (1.00)180 x 150 (1.20)

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
Error: Minified React error #418; visit https://react.dev/errors/418 for the full message or use the non-minified dev environment for full errors and additional helpful warnings. at t5 (https://bookshop.org/_next/static/chunks/fd9d1056-298733a1a5e2fe4a.js:1:24673) at iZ (https://bookshop.org/_next/static/chunks/fd9d1056-298733a1a5e2fe4a.js:1:120538) at ia (https://bookshop.org/_next/static/chunks/fd9d1056-298733a1a5e2fe4a.js:1:95165) at https://bookshop.org/_next/static/chunks/fd9d1056-298733a1a5e2fe4a.js:1:91091 at https://bookshop.org/_next/static/chunks/fd9d1056-298733a1a5e2fe4a.js:1:91098 at oZ (https://bookshop.org/_next/static/chunks/fd9d1056-298733a1a5e2fe4a.js:1:91203) at MessagePort.M (https://bookshop.org/_next/static/chunks/2117-a7c96d3f711e8b10.js:1:85058)
Error: Minified React error #418; visit https://react.dev/errors/418 for the full message or use the non-minified dev environment for full errors and additional helpful warnings. at t5 (https://bookshop.org/_next/static/chunks/fd9d1056-298733a1a5e2fe4a.js:1:24673) at iZ (https://bookshop.org/_next/static/chunks/fd9d1056-298733a1a5e2fe4a.js:1:120614) at ia (https://bookshop.org/_next/static/chunks/fd9d1056-298733a1a5e2fe4a.js:1:95165) at https://bookshop.org/_next/static/chunks/fd9d1056-298733a1a5e2fe4a.js:1:91091 at https://bookshop.org/_next/static/chunks/fd9d1056-298733a1a5e2fe4a.js:1:91098 at oZ (https://bookshop.org/_next/static/chunks/fd9d1056-298733a1a5e2fe4a.js:1:91203) at MessagePort.M (https://bookshop.org/_next/static/chunks/2117-a7c96d3f711e8b10.js:1:85058)
Error: Minified React error #418; visit https://react.dev/errors/418 for the full message or use the non-minified dev environment for full errors and additional helpful warnings. at t5 (https://bookshop.org/_next/static/chunks/fd9d1056-298733a1a5e2fe4a.js:1:24673) at iZ (https://bookshop.org/_next/static/chunks/fd9d1056-298733a1a5e2fe4a.js:1:120614) at ia (https://bookshop.org/_next/static/chunks/fd9d1056-298733a1a5e2fe4a.js:1:95165) at https://bookshop.org/_next/static/chunks/fd9d1056-298733a1a5e2fe4a.js:1:91091 at https://bookshop.org/_next/static/chunks/fd9d1056-298733a1a5e2fe4a.js:1:91098 at oZ (https://bookshop.org/_next/static/chunks/fd9d1056-298733a1a5e2fe4a.js:1:91203) at MessagePort.M (https://bookshop.org/_next/static/chunks/2117-a7c96d3f711e8b10.js:1:85058)
Error: Minified React error #418; visit https://react.dev/errors/418 for the full message or use the non-minified dev environment for full errors and additional helpful warnings. at t5 (https://bookshop.org/_next/static/chunks/fd9d1056-298733a1a5e2fe4a.js:1:24673) at iZ (https://bookshop.org/_next/static/chunks/fd9d1056-298733a1a5e2fe4a.js:1:120614) at ia (https://bookshop.org/_next/static/chunks/fd9d1056-298733a1a5e2fe4a.js:1:95165) at https://bookshop.org/_next/static/chunks/fd9d1056-298733a1a5e2fe4a.js:1:91091 at https://bookshop.org/_next/static/chunks/fd9d1056-298733a1a5e2fe4a.js:1:91098 at oZ (https://bookshop.org/_next/static/chunks/fd9d1056-298733a1a5e2fe4a.js:1:91203) at MessagePort.M (https://bookshop.org/_next/static/chunks/2117-a7c96d3f711e8b10.js:1:85058)
Error: Minified React error #418; visit https://react.dev/errors/418 for the full message or use the non-minified dev environment for full errors and additional helpful warnings. at t5 (https://bookshop.org/_next/static/chunks/fd9d1056-298733a1a5e2fe4a.js:1:24673) at iZ (https://bookshop.org/_next/static/chunks/fd9d1056-298733a1a5e2fe4a.js:1:120614) at ia (https://bookshop.org/_next/static/chunks/fd9d1056-298733a1a5e2fe4a.js:1:95165) at https://bookshop.org/_next/static/chunks/fd9d1056-298733a1a5e2fe4a.js:1:91091 at https://bookshop.org/_next/static/chunks/fd9d1056-298733a1a5e2fe4a.js:1:91098 at oZ (https://bookshop.org/_next/static/chunks/fd9d1056-298733a1a5e2fe4a.js:1:91203) at MessagePort.M (https://bookshop.org/_next/static/chunks/2117-a7c96d3f711e8b10.js:1:85058)
Error: Minified React error #418; visit https://react.dev/errors/418 for the full message or use the non-minified dev environment for full errors and additional helpful warnings. at t5 (https://bookshop.org/_next/static/chunks/fd9d1056-298733a1a5e2fe4a.js:1:24673) at iZ (https://bookshop.org/_next/static/chunks/fd9d1056-298733a1a5e2fe4a.js:1:120614) at ia (https://bookshop.org/_next/static/chunks/fd9d1056-298733a1a5e2fe4a.js:1:95165) at https://bookshop.org/_next/static/chunks/fd9d1056-298733a1a5e2fe4a.js:1:91091 at https://bookshop.org/_next/static/chunks/fd9d1056-298733a1a5e2fe4a.js:1:91098 at oZ (https://bookshop.org/_next/static/chunks/fd9d1056-298733a1a5e2fe4a.js:1:91203) at MessagePort.M (https://bookshop.org/_next/static/chunks/2117-a7c96d3f711e8b10.js:1:85058)
Error: Minified React error #418; visit https://react.dev/errors/418 for the full message or use the non-minified dev environment for full errors and additional helpful warnings. at t5 (https://bookshop.org/_next/static/chunks/fd9d1056-298733a1a5e2fe4a.js:1:24673) at iZ (https://bookshop.org/_next/static/chunks/fd9d1056-298733a1a5e2fe4a.js:1:120614) at ia (https://bookshop.org/_next/static/chunks/fd9d1056-298733a1a5e2fe4a.js:1:95165) at https://bookshop.org/_next/static/chunks/fd9d1056-298733a1a5e2fe4a.js:1:91091 at https://bookshop.org/_next/static/chunks/fd9d1056-298733a1a5e2fe4a.js:1:91098 at oZ (https://bookshop.org/_next/static/chunks/fd9d1056-298733a1a5e2fe4a.js:1:91203) at MessagePort.M (https://bookshop.org/_next/static/chunks/2117-a7c96d3f711e8b10.js:1:85058)
Error: Minified React error #418; visit https://react.dev/errors/418 for the full message or use the non-minified dev environment for full errors and additional helpful warnings. at t5 (https://bookshop.org/_next/static/chunks/fd9d1056-298733a1a5e2fe4a.js:1:24673) at iZ (https://bookshop.org/_next/static/chunks/fd9d1056-298733a1a5e2fe4a.js:1:120614) at ia (https://bookshop.org/_next/static/chunks/fd9d1056-298733a1a5e2fe4a.js:1:95165) at https://bookshop.org/_next/static/chunks/fd9d1056-298733a1a5e2fe4a.js:1:91091 at https://bookshop.org/_next/static/chunks/fd9d1056-298733a1a5e2fe4a.js:1:91098 at oZ (https://bookshop.org/_next/static/chunks/fd9d1056-298733a1a5e2fe4a.js:1:91203) at MessagePort.M (https://bookshop.org/_next/static/chunks/2117-a7c96d3f711e8b10.js:1:85058)
Error: Minified React error #423; visit https://react.dev/errors/423 for the full message or use the non-minified dev environment for full errors and additional helpful warnings. at iZ (https://bookshop.org/_next/static/chunks/fd9d1056-298733a1a5e2fe4a.js:1:118352) at ia (https://bookshop.org/_next/static/chunks/fd9d1056-298733a1a5e2fe4a.js:1:95165) at https://bookshop.org/_next/static/chunks/fd9d1056-298733a1a5e2fe4a.js:1:94987 at il (https://bookshop.org/_next/static/chunks/fd9d1056-298733a1a5e2fe4a.js:1:94994) at oJ (https://bookshop.org/_next/static/chunks/fd9d1056-298733a1a5e2fe4a.js:1:92350) at oZ (https://bookshop.org/_next/static/chunks/fd9d1056-298733a1a5e2fe4a.js:1:91769) at MessagePort.M (https://bookshop.org/_next/static/chunks/2117-a7c96d3f711e8b10.js:1:85058)
bookshop.org/ line 19, col 509079
TypeError: Cannot read properties of null (reading 'document') at HTMLDocument.c (https://bookshop.org/:20:509080)

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.

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
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
85

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.

Informative elements should aim for short, descriptive alternate text. Decorative elements can be ignored with an empty alt attribute. Learn more about the `alt` attribute.

Why this matters

Performance issues directly impact user engagement and conversion rates.

Failing Elements
body > img body > img

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
Document has a valid `hreflang`
Document has a valid `rel=canonical`

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