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.

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

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.styles__AppLayoutWrapperWithPadding-sc-ef9b07f2-7 > div.styles__AppLayoutMainContentMiddleRail-sc-ef9b07f2-11 > div.styles__HomePageV5Container-sc-509c1d3a-0 > div.styles__HomePageV5HeroBackgroundImage-sc-509c1d3a-8

path: 1,HTML,1,BODY,1,DIV,0,DIV,3,DIV,2,MAIN,0,DIV,0,DIV,0,DIV,0,DIV,0,DIV

selector: div.styles__AppLayoutWrapperWithPadding-sc-ef9b07f2-7 > div.styles__AppLayoutMainContentMiddleRail-sc-ef9b07f2-11 > div.styles__HomePageV5Container-sc-509c1d3a-0 > div.styles__HomePageV5HeroBackgroundImage-sc-509c1d3a-8

snippet: <div class="styles__HomePageV5HeroBackgroundImage-sc-509c1d3a-8 iqjIkX">

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.

More than 4 preconnect connections were found. These should be used sparingly and only to the most important origins.

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

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
www.bartleby.com/static/FooterSocialRailV2/bartleby-study-list-v2-800.jpg	0.0 ms	153.3 KiB
/static/FooterSocialRailV2/trapezoid-area-problem-example...	0.0 ms	122.4 KiB
www.bartleby.com/static/FooterSocialRailV2/bartleby-study-help-v2-800.jpg	0.0 ms	106.4 KiB
www.bartleby.com/static/FooterSocialRailV2/bartleby-study-help-v2-400.jpg	0.0 ms	106.4 KiB
www.bartleby.com/static/FooterSocialRailV2/bartleby-study-list-v2-600.jpg	0.0 ms	95.2 KiB
www.bartleby.com/static/homepage-v5/write-group-bg-mobile.png	0.0 ms	93.7 KiB
/static/FooterSocialRailV2/trapezoid-area-problem-example...	0.0 ms	86.9 KiB
www.bartleby.com/static/FooterSocialRailV2/bartleby-bned-bookstore-v2-800.jpg	0.0 ms	78.8 KiB
/static/FooterSocialRailV2/happy-national-thesauraus-day-...	0.0 ms	71.7 KiB
www.bartleby.com/static/FooterSocialRailV2/bartleby-study-help-v2-600.jpg	0.0 ms	71.1 KiB
www.bartleby.com/static/FooterSocialRailV2/bartleby-bned-bookstore-v2-600.jpg	0.0 ms	55.9 KiB
/static/FooterSocialRailV2/trapezoid-area-problem-example...	0.0 ms	51.9 KiB
/static/FooterSocialRailV2/happy-national-thesauraus-day-...	0.0 ms	51.4 KiB
www.bartleby.com/static/FooterSocialRailV2/bartleby-study-list-v2-400.jpg	0.0 ms	48.3 KiB
www.bartleby.com/static/FooterSocialRailV2/bartleby-website-v2-800.jpg	0.0 ms	47.3 KiB
www.bartleby.com/static/FooterSocialRailV2/bartleby-bned-bookstore-v2-400.jpg	0.0 ms	33.1 KiB
www.bartleby.com/static/FooterSocialRailV2/bartleby-website-v2-600.jpg	0.0 ms	32.7 KiB
/static/FooterSocialRailV2/happy-national-thesauraus-day-...	0.0 ms	31.2 KiB
www.bartleby.com/static/FooterSocialRailV2/bartleby-website-v2-400.jpg	0.0 ms	21.3 KiB
www.bartleby.com/static/subjectsV2/social-scienceV2.svg	0.0 ms	6.4 KiB
www.bartleby.com/static/third-party/google-play-badge-new.png	0.0 ms	4.3 KiB
www.bartleby.com/static/subjectsV2/engineeringV2.svg	0.0 ms	3.3 KiB
www.bartleby.com/static/subjectsV2/languageV2.svg	0.0 ms	3.2 KiB
www.bartleby.com/static/subjectsV2/businessV2.svg	0.0 ms	3.0 KiB
www.bartleby.com/static/homepage-v5/Icons/grammer-checker.svg	0.0 ms	2.0 KiB
www.bartleby.com/static/homepage-v5/Icons/paraphraser.svg	0.0 ms	1.7 KiB
www.bartleby.com/static/subjectsV2/scienceV2.svg	0.0 ms	1.6 KiB
www.bartleby.com/static/subjectsV2/mathV2.svg	0.0 ms	1.3 KiB
www.bartleby.com/static/homepage-v5/gradient-bg-round-2.svg	0.0 ms	1.2 KiB
www.bartleby.com/static/homepage-v5/gradient-bg-round-3.svg	0.0 ms	1.1 KiB
www.bartleby.com/static/homepage-v5/gradient-bg-round-4.svg	0.0 ms	1.1 KiB
/isbn_cover_images/9780133840544/9780133840544_smallCover...	604800.0 s	9.9 KiB
bartleby.com/textbook_empty_images/large_textbook_empty.svg	0.0 ms	1004 B
www.bartleby.com/static/homepage-v5/gradient-bg-round-5.svg	0.0 ms	937 B
www.bartleby.com/static/homepage-v5/gradient-bg-round-1.svg	0.0 ms	932 B
/isbn_cover_images/9780134041360/9780134041360_smallCover...	604800.0 s	8.5 KiB
www.bartleby.com/static/product-logos/bartleby-learn-logo-tm.svg	604800.0 s	8.5 KiB
/isbn_cover_images/9780134746241/9780134746241_smallCover...	604800.0 s	8.4 KiB
/isbn_cover_images/9780134392790/9780134392790_smallCover...	604800.0 s	7.6 KiB
/isbn_cover_images/9781118141809/9781118141809_smallCover...	604800.0 s	6.7 KiB
/isbn_cover_images/9780130970695/9780130970695_smallCover...	604800.0 s	6.2 KiB
/isbn_cover_images/9780134444321/9780134444321_smallCover...	604800.0 s	5.7 KiB
/isbn_cover_images/9780134802213/9780134802213_smallCover...	604800.0 s	5.1 KiB
www.bartleby.com/static/bartleby-logo-tm-tag-inverted.svg	604800.0 s	4.5 KiB
www.bartleby.com/static/apple-store-badge.svg	604800.0 s	4.3 KiB
/isbn_cover_images/9780134753119/9780134753119_smallCover...	604800.0 s	3.3 KiB
www.bartleby.com/static/bartleby-logo-tm.svg	604800.0 s	3.1 KiB
www.bartleby.com/static/social/footer-instagram-icon-white.svg	604800.0 s	1.7 KiB
www.bartleby.com/static/social/footer-twitter-icon-white.svg	604800.0 s	1.1 KiB
www.bartleby.com/static/social/footer-youtube-icon-white.svg	604800.0 s	1.0 KiB
www.bartleby.com/static/social/footer-facebook-icon-white.svg	604800.0 s	883 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.

	URL	Resource Size	Est Savings
div.styles__HomePageV5Container-sc-509c1d3a-0 > div.styles__HomePageV5OuterContentWrapper-sc-509c1d3a-1 > div.styles__HomePageV5WriteAndPopularWrapper-sc-509c1d3a-22 > div.styles__HomePageV5WriteAndPopularWrapperBg-sc-509c1d3a-23 `div.styles__HomePageV5Container-sc-509c1d3a-0 > div.styles__HomePageV5OuterContentWrapper-sc-509c1d3a-1 > div.styles__HomePageV5WriteAndPopularWrapper-sc-509c1d3a-22 > div.styles__HomePageV5WriteAndPopularWrapperBg-sc-509c1d3a-23`	www.bartleby.com/static/homepage-v5/write-group-bg-mobile.png	93.1 KiB	51.0 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: 805 ms

URL	Time Spent
bartleby.com/	805 ms
www.bartleby.com/	0.0 ms

Time to Interactive is the amount of time it takes for the page to become fully interactive. Learn more about the Time to Interactive metric.

Why this matters

Performance issues directly impact user engagement and conversion rates.

TTI

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 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: 150 ms 33.9 KiB

URL	Transfer Size	Est Savings
www.bartleby.com/_next/static/chunks/91036-5679ee51e38705e2.js	58.8 KiB	33.9 KiB

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

Why this matters

Performance issues directly impact user engagement and conversion rates.

Category	Time Spent
Script Evaluation	1.4 s
Other	673 ms
Style & Layout	356 ms
Script Parsing & Compilation	158 ms
Parse HTML & CSS	85 ms
Rendering	40 ms
Garbage Collection	27 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 22.8 KiB

URL	Transfer Size	Est Savings
	22.8 KiB	22.8 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

●LCP breakdown

●Modern HTTP

●Render blocking requests

●Optimize viewport for mobile

●Minify CSS

●Minify JavaScript

●Avoids enormous network payloads Total size was 2,285 KiB

●User Timing marks and measures 4 user timings

●JavaScript execution time 1.2 s

●Avoid long main-thread tasks 8 long tasks found

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

●Page didn't prevent back/forward cache restoration

●Network Requests

●Network Round Trip Times 100 ms

●Server Backend Latencies 60 ms

●Tasks

●Diagnostics

●Metrics

●Screenshot Thumbnails

●Final Screenshot

●Script Treemap Data

●Resources Summary

●Initial server response time was short Root document took 90 ms

○INP breakdown

○Avoid non-composited animations

○Avoid large layout shifts

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
COMPANY `div.styles__FooterTopContainer-sc-c16fac32-2 > div.styles__FooterTopLeftContainer-sc-c16fac32-4 > ul.styles__FooterTopContainerCol2-sc-c16fac32-10 > h6.styles__FooterVerticalNavListHeading-sc-c16fac32-27`

These are opportunities to improve keyboard navigation in your application.

Tables and lists

Screen readers have a specific way of announcing lists. Ensuring proper list structure aids screen reader output. Learn more about proper list structure.

Why this matters

Performance issues directly impact user engagement and conversion rates.

Failing Elements
COMPANY About FAQ Sitemap `div.styles__FooterContainer-sc-c16fac32-1 > div.styles__FooterTopContainer-sc-c16fac32-2 > div.styles__FooterTopLeftContainer-sc-c16fac32-4 > ul.styles__FooterTopContainerCol2-sc-c16fac32-10`
CONNECT Contact Bartleby Contact Research (Essays) Literature Guides Concept Ex… `div.styles__FooterContainer-sc-c16fac32-1 > div.styles__FooterTopContainer-sc-c16fac32-2 > div.styles__FooterTopLeftContainer-sc-c16fac32-4 > ul.styles__FooterTopContainerCol3-sc-c16fac32-11`
WRITING TOOLS Paraphrasing Tool Grammar Checker Punctuation Checker Spell Check… `div.styles__FooterContainer-sc-c16fac32-1 > div.styles__FooterTopContainer-sc-c16fac32-2 > div.styles__FooterTopLeftContainer-sc-c16fac32-4 > ul.styles__FooterTopVerticalNavList-sc-c16fac32-26`
LEGAL Copyright Policy Community Guidelines Academic Integrity Our Honor Code P… `div.styles__FooterContainer-sc-c16fac32-1 > div.styles__FooterTopContainer-sc-c16fac32-2 > div.styles__FooterTopLeftContainer-sc-c16fac32-4 > ul.styles__FooterTopVerticalNavList-sc-c16fac32-26`
bartleby, a Learneo, Inc. business `footer.styles__FooterWrapper-sc-c16fac32-0 > div.styles__FooterContainer-sc-c16fac32-1 > div.styles__FooterBottomContainer-sc-c16fac32-3 > ul.styles__FooterBottomLeftContainer-sc-c16fac32-7`

These are opportunities to improve the experience of reading tabular or list data using assistive technology, like a screen reader.

Best practices

Disabling zooming is problematic for users with low vision who rely on screen magnification to properly see the contents of a web page. Learn more about the viewport meta tag.

Why this matters

Informational: a Permissions-Policy directive showing feature -> allowed origins.

Source: MDN Permissions-Policy

Failing Elements
head > meta `head > meta`

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

●Buttons have an accessible name

●Image elements have `[alt]` attributes

●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

●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.

●Document has a main landmark.

●Deprecated ARIA roles were not used

●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.

○`[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

○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.

	URL	Aspect Ratio (Displayed)	Aspect Ratio (Actual)
Tutorials in Introductory Physics `div.styles__TextBookSingleItemSeperation-sc-b00a4e39-9 > div.styles__TextBookSingleItemInnerBox-sc-b00a4e39-10 > picture > img.styles__PictureFallbackImage-sc-6028e6d3-0`	/isbn_cover_images/9780130970695/9780130970695_smallCover...	87 x 98 (0.89)	100 x 100 (1.00)
Applied Statics and Strength of Materials (6th Edition) `div.styles__TextBookSingleItemSeperation-sc-b00a4e39-9 > div.styles__TextBookSingleItemInnerBox-sc-b00a4e39-10 > picture > img.styles__PictureFallbackImage-sc-6028e6d3-0`	/isbn_cover_images/9780133840544/9780133840544_smallCover...	87 x 98 (0.89)	100 x 100 (1.00)
Exercises for Weather & Climate (9th Edition) `div.styles__TextBookSingleItemSeperation-sc-b00a4e39-9 > div.styles__TextBookSingleItemInnerBox-sc-b00a4e39-10 > picture > img.styles__PictureFallbackImage-sc-6028e6d3-0`	/isbn_cover_images/9780134041360/9780134041360_smallCover...	87 x 98 (0.89)	100 x 100 (1.00)
Mathematics for Elementary Teachers with Activities (5th Edition) `div.styles__TextBookSingleItemSeperation-sc-b00a4e39-9 > div.styles__TextBookSingleItemInnerBox-sc-b00a4e39-10 > picture > img.styles__PictureFallbackImage-sc-6028e6d3-0`	/isbn_cover_images/9780134392790/9780134392790_smallCover...	87 x 98 (0.89)	100 x 100 (1.00)
Starting Out with Python (4th Edition) `div.styles__TextBookSingleItemSeperation-sc-b00a4e39-9 > div.styles__TextBookSingleItemInnerBox-sc-b00a4e39-10 > picture > img.styles__PictureFallbackImage-sc-6028e6d3-0`	/isbn_cover_images/9780134444321/9780134444321_smallCover...	87 x 98 (0.89)	100 x 100 (1.00)
Applications and Investigations in Earth Science (9th Edition) `div.styles__TextBookSingleItemSeperation-sc-b00a4e39-9 > div.styles__TextBookSingleItemInnerBox-sc-b00a4e39-10 > picture > img.styles__PictureFallbackImage-sc-6028e6d3-0`	/isbn_cover_images/9780134746241/9780134746241_smallCover...	87 x 98 (0.89)	100 x 100 (1.00)
A First Course in Probability (10th Edition) `div.styles__TextBookSingleItemSeperation-sc-b00a4e39-9 > div.styles__TextBookSingleItemInnerBox-sc-b00a4e39-10 > picture > img.styles__PictureFallbackImage-sc-6028e6d3-0`	/isbn_cover_images/9780134753119/9780134753119_smallCover...	87 x 98 (0.89)	100 x 100 (1.00)
Starting Out with Java: From Control Structures through Objects (7th Edition) (… `div.styles__TextBookSingleItemSeperation-sc-b00a4e39-9 > div.styles__TextBookSingleItemInnerBox-sc-b00a4e39-10 > picture > img.styles__PictureFallbackImage-sc-6028e6d3-0`	/isbn_cover_images/9780134802213/9780134802213_smallCover...	87 x 98 (0.89)	100 x 100 (1.00)
Introductory Mathematics for Engineering Applications `div.styles__TextBookSingleItemSeperation-sc-b00a4e39-9 > div.styles__TextBookSingleItemInnerBox-sc-b00a4e39-10 > picture > img.styles__PictureFallbackImage-sc-6028e6d3-0`	/isbn_cover_images/9781118141809/9781118141809_smallCover...	87 x 98 (0.89)	100 x 100 (1.00)
Download from Google play store `div.styles__FooterAppBadgeIcons-sc-c16fac32-13 > div.styles__AppIcons-sc-c16fac32-15 > a.BaseAnchorElementWithDisabledState__AnchorWithDisabledState-sc-4e9e1c9d-0 > img`	www.bartleby.com/static/third-party/google-play-badge-new.png	134 x 44 (3.05)	134 x 40 (3.35)
Download from Google play store `div.styles__FooterTopRightWrapper-sc-c16fac32-6 > div.styles__AppIcons-sc-c16fac32-15 > a.BaseAnchorElementWithDisabledState__AnchorWithDisabledState-sc-4e9e1c9d-0 > img`	www.bartleby.com/static/third-party/google-play-badge-new.png	134 x 44 (3.05)	134 x 40 (3.35)

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.

●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

●Page has valid source maps

○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`

Source	Description
www.bartleby.com/_next/static/chunks/framework-75746eeb80cbf23f.js line 8, col 46303	Error: Minified React error #418; visit https://reactjs.org/docs/error-decoder.html?invariant=418 for the full message or use the non-minified dev environment for full errors and additional helpful warnings. at lh (https://www.bartleby.com/_next/static/chunks/framework-75746eeb80cbf23f.js:9:46304) at i (https://www.bartleby.com/_next/static/chunks/framework-75746eeb80cbf23f.js:9:121161) at oO (https://www.bartleby.com/_next/static/chunks/framework-75746eeb80cbf23f.js:9:99114) at https://www.bartleby.com/_next/static/chunks/framework-75746eeb80cbf23f.js:9:98981 at oF (https://www.bartleby.com/_next/static/chunks/framework-75746eeb80cbf23f.js:9:98988) at oS (https://www.bartleby.com/_next/static/chunks/framework-75746eeb80cbf23f.js:9:94027) at x (https://www.bartleby.com/_next/static/chunks/framework-75746eeb80cbf23f.js:33:1373) at MessagePort.T (https://www.bartleby.com/_next/static/chunks/framework-75746eeb80cbf23f.js:33:1903)
www.bartleby.com/_next/static/chunks/framework-75746eeb80cbf23f.js line 8, col 46303	Error: Minified React error #418; visit https://reactjs.org/docs/error-decoder.html?invariant=418 for the full message or use the non-minified dev environment for full errors and additional helpful warnings. at lh (https://www.bartleby.com/_next/static/chunks/framework-75746eeb80cbf23f.js:9:46304) at i (https://www.bartleby.com/_next/static/chunks/framework-75746eeb80cbf23f.js:9:121161) at oO (https://www.bartleby.com/_next/static/chunks/framework-75746eeb80cbf23f.js:9:99114) at https://www.bartleby.com/_next/static/chunks/framework-75746eeb80cbf23f.js:9:98981 at oF (https://www.bartleby.com/_next/static/chunks/framework-75746eeb80cbf23f.js:9:98988) at oS (https://www.bartleby.com/_next/static/chunks/framework-75746eeb80cbf23f.js:9:94027) at x (https://www.bartleby.com/_next/static/chunks/framework-75746eeb80cbf23f.js:33:1373) at MessagePort.T (https://www.bartleby.com/_next/static/chunks/framework-75746eeb80cbf23f.js:33:1903)
www.bartleby.com/_next/static/chunks/framework-75746eeb80cbf23f.js line 8, col 46303	Error: Minified React error #418; visit https://reactjs.org/docs/error-decoder.html?invariant=418 for the full message or use the non-minified dev environment for full errors and additional helpful warnings. at lh (https://www.bartleby.com/_next/static/chunks/framework-75746eeb80cbf23f.js:9:46304) at i (https://www.bartleby.com/_next/static/chunks/framework-75746eeb80cbf23f.js:9:121161) at oO (https://www.bartleby.com/_next/static/chunks/framework-75746eeb80cbf23f.js:9:99114) at https://www.bartleby.com/_next/static/chunks/framework-75746eeb80cbf23f.js:9:98981 at oF (https://www.bartleby.com/_next/static/chunks/framework-75746eeb80cbf23f.js:9:98988) at oS (https://www.bartleby.com/_next/static/chunks/framework-75746eeb80cbf23f.js:9:94027) at x (https://www.bartleby.com/_next/static/chunks/framework-75746eeb80cbf23f.js:33:1373) at MessagePort.T (https://www.bartleby.com/_next/static/chunks/framework-75746eeb80cbf23f.js:33:1903)
www.bartleby.com/_next/static/chunks/framework-75746eeb80cbf23f.js line 8, col 46303	Error: Minified React error #418; visit https://reactjs.org/docs/error-decoder.html?invariant=418 for the full message or use the non-minified dev environment for full errors and additional helpful warnings. at lh (https://www.bartleby.com/_next/static/chunks/framework-75746eeb80cbf23f.js:9:46304) at i (https://www.bartleby.com/_next/static/chunks/framework-75746eeb80cbf23f.js:9:121161) at oO (https://www.bartleby.com/_next/static/chunks/framework-75746eeb80cbf23f.js:9:99114) at https://www.bartleby.com/_next/static/chunks/framework-75746eeb80cbf23f.js:9:98981 at oF (https://www.bartleby.com/_next/static/chunks/framework-75746eeb80cbf23f.js:9:98988) at oS (https://www.bartleby.com/_next/static/chunks/framework-75746eeb80cbf23f.js:9:94027) at x (https://www.bartleby.com/_next/static/chunks/framework-75746eeb80cbf23f.js:33:1373) at MessagePort.T (https://www.bartleby.com/_next/static/chunks/framework-75746eeb80cbf23f.js:33:1903)
www.bartleby.com/_next/static/chunks/framework-75746eeb80cbf23f.js line 8, col 46303	Error: Minified React error #418; visit https://reactjs.org/docs/error-decoder.html?invariant=418 for the full message or use the non-minified dev environment for full errors and additional helpful warnings. at lh (https://www.bartleby.com/_next/static/chunks/framework-75746eeb80cbf23f.js:9:46304) at i (https://www.bartleby.com/_next/static/chunks/framework-75746eeb80cbf23f.js:9:121161) at oO (https://www.bartleby.com/_next/static/chunks/framework-75746eeb80cbf23f.js:9:99114) at https://www.bartleby.com/_next/static/chunks/framework-75746eeb80cbf23f.js:9:98981 at oF (https://www.bartleby.com/_next/static/chunks/framework-75746eeb80cbf23f.js:9:98988) at oS (https://www.bartleby.com/_next/static/chunks/framework-75746eeb80cbf23f.js:9:94027) at x (https://www.bartleby.com/_next/static/chunks/framework-75746eeb80cbf23f.js:33:1373) at MessagePort.T (https://www.bartleby.com/_next/static/chunks/framework-75746eeb80cbf23f.js:33:1903)
www.bartleby.com/_next/static/chunks/framework-75746eeb80cbf23f.js line 8, col 46303	Error: Minified React error #418; visit https://reactjs.org/docs/error-decoder.html?invariant=418 for the full message or use the non-minified dev environment for full errors and additional helpful warnings. at lh (https://www.bartleby.com/_next/static/chunks/framework-75746eeb80cbf23f.js:9:46304) at i (https://www.bartleby.com/_next/static/chunks/framework-75746eeb80cbf23f.js:9:121161) at oO (https://www.bartleby.com/_next/static/chunks/framework-75746eeb80cbf23f.js:9:99114) at https://www.bartleby.com/_next/static/chunks/framework-75746eeb80cbf23f.js:9:98981 at oF (https://www.bartleby.com/_next/static/chunks/framework-75746eeb80cbf23f.js:9:98988) at oS (https://www.bartleby.com/_next/static/chunks/framework-75746eeb80cbf23f.js:9:94027) at x (https://www.bartleby.com/_next/static/chunks/framework-75746eeb80cbf23f.js:33:1373) at MessagePort.T (https://www.bartleby.com/_next/static/chunks/framework-75746eeb80cbf23f.js:33:1903)
www.bartleby.com/_next/static/chunks/framework-75746eeb80cbf23f.js line 8, col 46303	Error: Minified React error #418; visit https://reactjs.org/docs/error-decoder.html?invariant=418 for the full message or use the non-minified dev environment for full errors and additional helpful warnings. at lh (https://www.bartleby.com/_next/static/chunks/framework-75746eeb80cbf23f.js:9:46304) at i (https://www.bartleby.com/_next/static/chunks/framework-75746eeb80cbf23f.js:9:121161) at oO (https://www.bartleby.com/_next/static/chunks/framework-75746eeb80cbf23f.js:9:99114) at https://www.bartleby.com/_next/static/chunks/framework-75746eeb80cbf23f.js:9:98981 at oF (https://www.bartleby.com/_next/static/chunks/framework-75746eeb80cbf23f.js:9:98988) at oS (https://www.bartleby.com/_next/static/chunks/framework-75746eeb80cbf23f.js:9:94027) at x (https://www.bartleby.com/_next/static/chunks/framework-75746eeb80cbf23f.js:33:1373) at MessagePort.T (https://www.bartleby.com/_next/static/chunks/framework-75746eeb80cbf23f.js:33:1903)
www.bartleby.com/_next/static/chunks/framework-75746eeb80cbf23f.js line 8, col 46303	Error: Minified React error #418; visit https://reactjs.org/docs/error-decoder.html?invariant=418 for the full message or use the non-minified dev environment for full errors and additional helpful warnings. at lh (https://www.bartleby.com/_next/static/chunks/framework-75746eeb80cbf23f.js:9:46304) at i (https://www.bartleby.com/_next/static/chunks/framework-75746eeb80cbf23f.js:9:121161) at oO (https://www.bartleby.com/_next/static/chunks/framework-75746eeb80cbf23f.js:9:99114) at https://www.bartleby.com/_next/static/chunks/framework-75746eeb80cbf23f.js:9:98981 at oF (https://www.bartleby.com/_next/static/chunks/framework-75746eeb80cbf23f.js:9:98988) at oS (https://www.bartleby.com/_next/static/chunks/framework-75746eeb80cbf23f.js:9:94027) at x (https://www.bartleby.com/_next/static/chunks/framework-75746eeb80cbf23f.js:33:1373) at MessagePort.T (https://www.bartleby.com/_next/static/chunks/framework-75746eeb80cbf23f.js:33:1903)
www.bartleby.com/_next/static/chunks/framework-75746eeb80cbf23f.js line 8, col 46303	Error: Minified React error #418; visit https://reactjs.org/docs/error-decoder.html?invariant=418 for the full message or use the non-minified dev environment for full errors and additional helpful warnings. at lh (https://www.bartleby.com/_next/static/chunks/framework-75746eeb80cbf23f.js:9:46304) at i (https://www.bartleby.com/_next/static/chunks/framework-75746eeb80cbf23f.js:9:121161) at oO (https://www.bartleby.com/_next/static/chunks/framework-75746eeb80cbf23f.js:9:99114) at https://www.bartleby.com/_next/static/chunks/framework-75746eeb80cbf23f.js:9:98981 at oF (https://www.bartleby.com/_next/static/chunks/framework-75746eeb80cbf23f.js:9:98988) at oS (https://www.bartleby.com/_next/static/chunks/framework-75746eeb80cbf23f.js:9:94027) at x (https://www.bartleby.com/_next/static/chunks/framework-75746eeb80cbf23f.js:33:1373) at MessagePort.T (https://www.bartleby.com/_next/static/chunks/framework-75746eeb80cbf23f.js:33:1903)
www.bartleby.com/_next/static/chunks/framework-75746eeb80cbf23f.js line 8, col 46303	Error: Minified React error #418; visit https://reactjs.org/docs/error-decoder.html?invariant=418 for the full message or use the non-minified dev environment for full errors and additional helpful warnings. at lh (https://www.bartleby.com/_next/static/chunks/framework-75746eeb80cbf23f.js:9:46304) at i (https://www.bartleby.com/_next/static/chunks/framework-75746eeb80cbf23f.js:9:121161) at oO (https://www.bartleby.com/_next/static/chunks/framework-75746eeb80cbf23f.js:9:99114) at https://www.bartleby.com/_next/static/chunks/framework-75746eeb80cbf23f.js:9:98981 at oF (https://www.bartleby.com/_next/static/chunks/framework-75746eeb80cbf23f.js:9:98988) at oS (https://www.bartleby.com/_next/static/chunks/framework-75746eeb80cbf23f.js:9:94027) at x (https://www.bartleby.com/_next/static/chunks/framework-75746eeb80cbf23f.js:33:1373) at MessagePort.T (https://www.bartleby.com/_next/static/chunks/framework-75746eeb80cbf23f.js:33:1903)
www.bartleby.com/_next/static/chunks/framework-75746eeb80cbf23f.js line 8, col 46303	Error: Minified React error #418; visit https://reactjs.org/docs/error-decoder.html?invariant=418 for the full message or use the non-minified dev environment for full errors and additional helpful warnings. at lh (https://www.bartleby.com/_next/static/chunks/framework-75746eeb80cbf23f.js:9:46304) at i (https://www.bartleby.com/_next/static/chunks/framework-75746eeb80cbf23f.js:9:121161) at oO (https://www.bartleby.com/_next/static/chunks/framework-75746eeb80cbf23f.js:9:99114) at https://www.bartleby.com/_next/static/chunks/framework-75746eeb80cbf23f.js:9:98981 at oF (https://www.bartleby.com/_next/static/chunks/framework-75746eeb80cbf23f.js:9:98988) at oS (https://www.bartleby.com/_next/static/chunks/framework-75746eeb80cbf23f.js:9:94027) at x (https://www.bartleby.com/_next/static/chunks/framework-75746eeb80cbf23f.js:33:1373) at MessagePort.T (https://www.bartleby.com/_next/static/chunks/framework-75746eeb80cbf23f.js:33:1903)
www.bartleby.com/_next/static/chunks/framework-75746eeb80cbf23f.js line 8, col 46303	Error: Minified React error #418; visit https://reactjs.org/docs/error-decoder.html?invariant=418 for the full message or use the non-minified dev environment for full errors and additional helpful warnings. at lh (https://www.bartleby.com/_next/static/chunks/framework-75746eeb80cbf23f.js:9:46304) at i (https://www.bartleby.com/_next/static/chunks/framework-75746eeb80cbf23f.js:9:121161) at oO (https://www.bartleby.com/_next/static/chunks/framework-75746eeb80cbf23f.js:9:99114) at https://www.bartleby.com/_next/static/chunks/framework-75746eeb80cbf23f.js:9:98981 at oF (https://www.bartleby.com/_next/static/chunks/framework-75746eeb80cbf23f.js:9:98988) at oS (https://www.bartleby.com/_next/static/chunks/framework-75746eeb80cbf23f.js:9:94027) at x (https://www.bartleby.com/_next/static/chunks/framework-75746eeb80cbf23f.js:33:1373) at MessagePort.T (https://www.bartleby.com/_next/static/chunks/framework-75746eeb80cbf23f.js:33:1903)
www.bartleby.com/_next/static/chunks/framework-75746eeb80cbf23f.js line 8, col 46303	Error: Minified React error #418; visit https://reactjs.org/docs/error-decoder.html?invariant=418 for the full message or use the non-minified dev environment for full errors and additional helpful warnings. at lh (https://www.bartleby.com/_next/static/chunks/framework-75746eeb80cbf23f.js:9:46304) at i (https://www.bartleby.com/_next/static/chunks/framework-75746eeb80cbf23f.js:9:121161) at oO (https://www.bartleby.com/_next/static/chunks/framework-75746eeb80cbf23f.js:9:99114) at https://www.bartleby.com/_next/static/chunks/framework-75746eeb80cbf23f.js:9:98981 at oF (https://www.bartleby.com/_next/static/chunks/framework-75746eeb80cbf23f.js:9:98988) at oS (https://www.bartleby.com/_next/static/chunks/framework-75746eeb80cbf23f.js:9:94027) at x (https://www.bartleby.com/_next/static/chunks/framework-75746eeb80cbf23f.js:33:1373) at MessagePort.T (https://www.bartleby.com/_next/static/chunks/framework-75746eeb80cbf23f.js:33:1903)
www.bartleby.com/_next/static/chunks/framework-75746eeb80cbf23f.js line 8, col 46757	Error: Minified React error #418; visit https://reactjs.org/docs/error-decoder.html?invariant=418 for the full message or use the non-minified dev environment for full errors and additional helpful warnings. at lv (https://www.bartleby.com/_next/static/chunks/framework-75746eeb80cbf23f.js:9:46758) at https://www.bartleby.com/_next/static/chunks/framework-75746eeb80cbf23f.js:9:100006 at oD (https://www.bartleby.com/_next/static/chunks/framework-75746eeb80cbf23f.js:9:106226) at oO (https://www.bartleby.com/_next/static/chunks/framework-75746eeb80cbf23f.js:9:99174) at https://www.bartleby.com/_next/static/chunks/framework-75746eeb80cbf23f.js:9:98981 at oF (https://www.bartleby.com/_next/static/chunks/framework-75746eeb80cbf23f.js:9:98988) at oS (https://www.bartleby.com/_next/static/chunks/framework-75746eeb80cbf23f.js:9:94027) at x (https://www.bartleby.com/_next/static/chunks/framework-75746eeb80cbf23f.js:33:1373) at MessagePort.T (https://www.bartleby.com/_next/static/chunks/framework-75746eeb80cbf23f.js:33:1903)
www.bartleby.com/_next/static/chunks/framework-75746eeb80cbf23f.js line 8, col 120829	Error: Minified React error #423; visit https://reactjs.org/docs/error-decoder.html?invariant=423 for the full message or use the non-minified dev environment for full errors and additional helpful warnings. at i (https://www.bartleby.com/_next/static/chunks/framework-75746eeb80cbf23f.js:9:120830) at oO (https://www.bartleby.com/_next/static/chunks/framework-75746eeb80cbf23f.js:9:99114) at https://www.bartleby.com/_next/static/chunks/framework-75746eeb80cbf23f.js:9:98981 at oF (https://www.bartleby.com/_next/static/chunks/framework-75746eeb80cbf23f.js:9:98988) at ox (https://www.bartleby.com/_next/static/chunks/framework-75746eeb80cbf23f.js:9:95740) at oS (https://www.bartleby.com/_next/static/chunks/framework-75746eeb80cbf23f.js:9:94295) at x (https://www.bartleby.com/_next/static/chunks/framework-75746eeb80cbf23f.js:33:1373) at MessagePort.T (https://www.bartleby.com/_next/static/chunks/framework-75746eeb80cbf23f.js:33:1903)