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Lighthouse Desktop

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

Audit breakdown by category with detailed findings.

79

Performance

Insights

Remove large, duplicate JavaScript modules from bundles to reduce unnecessary bytes consumed by network activity.

Why this matters

Performance issues directly impact user engagement and conversion rates.

Polyfills and transforms enable older browsers to use new JavaScript features. However, many aren't necessary for modern browsers. Consider modifying your JavaScript build process to not transpile Baseline features, unless you know you must support older browsers. Learn why most sites can deploy ES6+ code without transpiling

Why this matters

Performance issues directly impact user engagement and conversion rates.

3rd party code can significantly impact load performance. Reduce and defer loading of 3rd party code to prioritize your page's content.

Why this matters

Performance issues directly impact user engagement and conversion rates.

A long cache lifetime can speed up repeat visits to your page. Learn more about caching.

Why this matters

Performance issues directly impact user engagement and conversion rates.

RequestCache TTLTransfer Size
/photos/1280x720/1A2D5B63-0E6C-6D05-4B6F5FE1B2B7CEDA.jpg36000.0 s581.7 KiB
cdn.universityrelations.cornell.edu/images/research-2025.jpg0.0 ms121.8 KiB
/photos/400x225/97ED1A7B-A4EA-2A1D-0682FB1FC93E4312.jpg36000.0 s213.3 KiB
/photos/360x360/AA85866B-C44E-42F6-24C93F3A6A54E260.jpg0.0 ms114.0 KiB
/photos/360x360/AA35CCCB-A98C-F255-3FB3D87C97A41615.jpg36000.0 s188.6 KiB
/photos/360x360/AA427B20-D637-6D0E-190A5C495943239C.jpg36000.0 s179.9 KiB
/photos/360x360/AA505462-AF6E-14EB-391E7B23F0B05978.jpg36000.0 s171.0 KiB
/photos/360x360/1A07FF21-BAD7-6A1C-BB7C63EB8210FBE7.jpg36000.0 s120.5 KiB
/photos/400x225/850FCA14-9FD4-867A-6CD5A1621A680F3E.jpg0.0 ms65.8 KiB
/photos/360x360/AA714B42-BFFF-B6A8-02E0E198925385AC.jpg36000.0 s110.7 KiB
/photos/360x360/959BCAAF-FC30-8716-A3B213D64FE3D41A.jpg36000.0 s108.4 KiB
/photos/360x360/F4FD8094-E12B-0957-5E262F301DDD8B91.jpg36000.0 s97.2 KiB
/photos/360x360/A746AA91-F77D-AB4C-9F141556580C6E4C.jpg36000.0 s87.0 KiB
/photos/360x360/60EBEEC5-CE92-845C-74B7376D643E24EB.jpg0.0 ms47.3 KiB
/photos/360x360/AB69298D-A62D-B445-9A92E772C3BAD9DD.jpg36000.0 s82.6 KiB
/photos/400x225/AA664986-C9E4-E7DB-D5AC14ED3C2BCD8D.jpg36000.0 s79.5 KiB
/photos/400x225/4F45AC93-09A5-5E26-B59B80F5D7E369F3.jpg36000.0 s77.8 KiB
/photos/360x360/76583D5F-E4A2-0A6C-F49C1FC9E7067410.jpg36000.0 s74.0 KiB
/photos/360x360/CBEDE10A-9C64-465F-AC30FBF6802F84F3.jpg36000.0 s68.5 KiB
/photos/360x360/A1D836A8-CC07-608E-7D68529F791B6AA9.jpg36000.0 s62.1 KiB
/photos/360x360/302DED93-F593-9467-3E522A81AC61C14B.jpg36000.0 s54.0 KiB
/photos/360x360/8BB745DD-F57F-EC7B-13CA4386B1D18703.jpg36000.0 s39.3 KiB
ssl.google-analytics.com/ga.js7200.0 s17.4 KiB
media.univcomm.cornell.edu/photos/campaign/TDTGG.png7200.0 s12.2 KiB
use.typekit.net/gog6dck.js600.0 s7.0 KiB
siteimproveanalytics.com/js/siteanalyze_6120104.js86400.0 s13.3 KiB
/p.gif?s=1&k=gog6dck&ht=tk&h=www.cornell.edu&f=10954.1345...604800.0 s206 B

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.

URLEst Savings
www.cornell.edu/assets/core/fonts/fontcustom.woff615 ms
use.typekit.net/af/1aea0d/000000000000000000012106/27/l?subset_id=2&fvd=n3&v=315 ms
use.typekit.net/af/8dd886/000000000000000000010b5c/27/l?subset_id=2&fvd=n5&v=310 ms
use.typekit.net/af/1709eb/000000000000000000010b60/27/l?subset_id=2&fvd=n7&v=310 ms
use.typekit.net/af/cef9f3/000000000000000000010b5e/27/l?subset_id=2&fvd=n6&v=310 ms
use.typekit.net/af/ac6334/000000000000000000012059/27/l?subset_id=2&fvd=n4&v=35.0 ms
use.typekit.net/af/ba2099/000000000000000000010b58/27/l?subset_id=2&fvd=n3&v=35.0 ms
use.typekit.net/af/04ec74/00000000000000000001205b/27/l?subset_id=2&fvd=n7&v=35.0 ms
use.typekit.net/af/8cf83d/00000000000000000001205c/27/l?subset_id=2&fvd=i7&v=35.0 ms
use.typekit.net/af/2d5f33/000000000000000000012107/27/l?subset_id=2&fvd=i3&v=35.0 ms

Reducing the download time of images can improve the perceived load time of the page and LCP. Learn more about optimizing image size

Why this matters

Performance issues directly impact user engagement and conversion rates.

URLResource SizeEst Savings
Spring cold snaps harm nesting tree swallows, but some show resilience div#main > div.marquee-mask > div.marquee > span#panobg-1A21C5EA-D9C3-DB12-5E04B41C36D9F705
/photos/1280x720/1A2D5B63-0E6C-6D05-4B6F5FE1B2B7CEDA.jpg580.9 KiB430.9 KiB
Cornellian walking through the arch at the Cornell War Memorial on a sunny day. a.socialmedia-grid-link > div.socialmedia-grid > div.socialmedia-item > img
/photos/400x225/97ED1A7B-A4EA-2A1D-0682FB1FC93E4312.jpg212.8 KiB198.5 KiB
Three Cornellians sit on the Cornell Libe Slope on a warm March day. a.socialmedia-grid-link > div.socialmedia-grid > div.socialmedia-item > img
/photos/360x360/AA35CCCB-A98C-F255-3FB3D87C97A41615.jpg188.2 KiB179.9 KiB
A Cornell University student sits in a tree on the Cornell University Arts Quad. a.socialmedia-grid-link > div.socialmedia-grid > div.socialmedia-item > img
/photos/360x360/AA427B20-D637-6D0E-190A5C495943239C.jpg179.5 KiB177.5 KiB
Four Cornell University students walk along a path on the Cornell University Ar… a.socialmedia-grid-link > div.socialmedia-grid > div.socialmedia-item > img
/photos/360x360/AA505462-AF6E-14EB-391E7B23F0B05978.jpg170.6 KiB168.6 KiB
The reflection of cherry blossoms seen in a window of Cornell's Sage Hall. a.socialmedia-grid-link > div.socialmedia-grid > div.socialmedia-item > img
/photos/360x360/AA714B42-BFFF-B6A8-02E0E198925385AC.jpg110.4 KiB108.4 KiB
A Cornell University student works on a sewing machine. a.socialmedia-grid-link > div.socialmedia-grid > div.socialmedia-item > img
/photos/360x360/AA85866B-C44E-42F6-24C93F3A6A54E260.jpg113.6 KiB105.3 KiB
Ezra Cornell statue imposed over a red background in front of a large floating … body.home > div#campaign > img#campaignCoverImg
www.cornell.edu/assets/images/campaign/ezra.jpg219.6 KiB102.3 KiB
div.home-honeycomb > div#honeycomb > a.hc-item > img.image-replace div.home-honeycomb > div#honeycomb > a.hc-item > img.image-replace
/photos/360x360/1A07FF21-BAD7-6A1C-BB7C63EB8210FBE7.jpg120.1 KiB101.6 KiB
Cornellian operating a dril press. a.socialmedia-grid-link > div.socialmedia-grid > div.socialmedia-item > img
/photos/360x360/F4FD8094-E12B-0957-5E262F301DDD8B91.jpg96.9 KiB94.9 KiB
Cornell's McGraw Tower, framed by cherry leaves, against a brilliant blue sky. a.socialmedia-grid-link > div.socialmedia-grid > div.socialmedia-item > img
/photos/400x225/AA664986-C9E4-E7DB-D5AC14ED3C2BCD8D.jpg79.2 KiB74.5 KiB
div.home-honeycomb > div#honeycomb > a.hc-item > img.image-replace div.home-honeycomb > div#honeycomb > a.hc-item > img.image-replace
/photos/360x360/A746AA91-F77D-AB4C-9F141556580C6E4C.jpg86.7 KiB68.1 KiB
Students perform a wet aggregate stability experiment. div.slide-mask > div.slideshow > a.grid-box > img.image-replace
/photos/400x225/4F45AC93-09A5-5E26-B59B80F5D7E369F3.jpg77.5 KiB64.5 KiB
div.home-honeycomb > div#honeycomb > a.hc-item > img.image-replace div.home-honeycomb > div#honeycomb > a.hc-item > img.image-replace
/photos/360x360/AB69298D-A62D-B445-9A92E772C3BAD9DD.jpg82.3 KiB63.8 KiB
div.home-honeycomb > div#honeycomb > a.hc-item > img.image-replace div.home-honeycomb > div#honeycomb > a.hc-item > img.image-replace
/photos/360x360/76583D5F-E4A2-0A6C-F49C1FC9E7067410.jpg73.7 KiB55.2 KiB
Gavin Sacks. div.slide-mask > div.slideshow > a.grid-box > img.image-replace
/photos/400x225/850FCA14-9FD4-867A-6CD5A1621A680F3E.jpg65.6 KiB52.6 KiB
A video of collage of various Cornell reasearhers and their work. div > div#cover-area > div#cover-video > video#cover-vid
cdn.universityrelations.cornell.edu/images/research-2025.jpg121.1 KiB51.1 KiB
body.home > header#cu-hdr > div.cu-hdr-inner > a#cu-brand body.home > header#cu-hdr > div.cu-hdr-inner > a#cu-brand
www.cornell.edu/assets/core/images/logo-red@2x.png24.5 KiB13.9 KiB
To do he greatest good: The Campaign for Cornell University li.ftr-item > div.ftr-item-campaign > a > img
media.univcomm.cornell.edu/photos/campaign/TDTGG.png12.8 KiB7.2 KiB

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-SPAN
nodeLabel: Spring cold snaps harm nesting tree swallows, but some show resilience
path: 5,HTML,2,BODY,9,DIV,1,DIV,2,DIV,0,SPAN
selector: div#main > div.marquee-mask > div.marquee > span#panobg-1A21C5EA-D9C3-DB12-5E04B41C36D9F705
snippet: <span id="panobg-1A21C5EA-D9C3-DB12-5E04B41C36D9F705" class="marquee-item gradientAdjustTop0p gradientAdjustBottom0p marquee-position-2…" style="position: absolute; left: 0px; top: 0px; display: block;" data-counter="1" data-click-label="1|1A21C5EA-D9C3-DB12-5E04B41C36D9F705|A62E1FAC-D576-86BF-7C3668F54F14A928|…" data-click-action="pano | content">

Avoid chaining critical requests by reducing the length of chains, reducing the download size of resources, or deferring the download of unnecessary resources to improve page load.

Why this matters

Performance issues directly impact user engagement and conversion rates.

description: [preconnect](https://developer.chrome.com/docs/lighthouse/performance/uses-rel-preconnect/) hints help the browser establish a connection earlier in the page load, saving time when the first request for that origin is made. The following are the origins that the page preconnected to.
title: Preconnected origins
value: no origins were preconnected
description: Add [preconnect](https://developer.chrome.com/docs/lighthouse/performance/uses-rel-preconnect/) hints to your most important origins, but try to use no more than 4.
title: Preconnect candidates

Requests are blocking the page's initial render, which may delay LCP. Deferring or inlining can move these network requests out of the critical path.

Why this matters

Performance issues directly impact user engagement and conversion rates.

URLTransfer SizeDuration
www.cornell.edu/assets/core/css/cornell.css?ver=2025051245.4 KiB113 ms
www.cornell.edu/assets/css/style.css?ver=2025051212.4 KiB56 ms
www.cornell.edu/assets/core/js/lib/modernizr.js?ver=202505126.4 KiB
use.typekit.net/gog6dck.js7.0 KiB
www.cornell.edu/assets/css/print.css?ver=20250512694 B
www.cornell.edu/assets/css/social-grid.css1.2 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: 521 ms
URLTime Spent
cornell.edu/521 ms
www.cornell.edu/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

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: 90 ms 46.7 KiB
URLTransfer SizeEst Savings
www.cornell.edu/assets/core/css/cornell.css?ver=2025051245.1 KiB36.0 KiB
www.cornell.edu/assets/css/style.css?ver=2025051212.1 KiB10.7 KiB

Reduce unused JavaScript and defer loading scripts until they are required to decrease bytes consumed by network activity. Learn how to reduce unused JavaScript.

Why this matters

Performance issues directly impact user engagement and conversion rates.

Estimated savings: 260 ms 241.8 KiB
URLTransfer SizeEst Savings
www.googletagmanager.com/gtag/js?id=G-PMZ19X3F8W&cx=c&gtm=4e64f0156.4 KiB110.4 KiB
www.googletagmanager.com/gtag/js?id=G-PMZ19X3F8W156.4 KiB67.2 KiB
www.googletagmanager.com/gtm.js?id=GTM-WW83RG9127.1 KiB64.2 KiB

Minifying CSS files can reduce network payload sizes. Learn how to minify CSS.

Why this matters

Performance issues directly impact user engagement and conversion rates.

Estimated savings: 0.0 ms 12.8 KiB
URLTransfer SizeEst Savings
www.cornell.edu/assets/core/css/cornell.css?ver=2025051245.4 KiB9.0 KiB
www.cornell.edu/assets/css/style.css?ver=2025051212.4 KiB3.8 KiB

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

Why this matters

Performance issues directly impact user engagement and conversion rates.

Estimated savings: 0.0 ms 10.9 KiB
URLTransfer SizeEst Savings
www.cornell.edu/assets/core/js/lib/plugins.js9.9 KiB4.9 KiB
www.cornell.edu/assets/core/js/cornell.js?ver=20191023a9.5 KiB3.3 KiB
www.cornell.edu/assets/js/cornelledu.js?ver=20230613a7.1 KiB2.6 KiB

Large network payloads cost users real money and are highly correlated with long load times. Learn how to reduce payload sizes.

Why this matters

Performance issues directly impact user engagement and conversion rates.

URLTransfer Size
/p/537811/sp/53781100/download/entry_id/1_6qqtj7t8/flavor...8.6 MiB
/p/537811/sp/53781100/download/entry_id/0_xlka3d02/flavor...4.9 MiB
/photos/1280x720/1A2D5B63-0E6C-6D05-4B6F5FE1B2B7CEDA.jpg581.7 KiB
/photos/400x225/97ED1A7B-A4EA-2A1D-0682FB1FC93E4312.jpg213.3 KiB
www.cornell.edu/assets/images/campaign/ezra.jpg202.3 KiB
/photos/360x360/AA35CCCB-A98C-F255-3FB3D87C97A41615.jpg188.6 KiB
/photos/360x360/AA427B20-D637-6D0E-190A5C495943239C.jpg179.9 KiB
/photos/360x360/AA505462-AF6E-14EB-391E7B23F0B05978.jpg171.0 KiB
www.googletagmanager.com/gtag/js?id=G-PMZ19X3F8W156.7 KiB
www.googletagmanager.com/gtag/js?id=G-PMZ19X3F8W&cx=c&gtm=4e64f0156.5 KiB

Set an explicit width and height on image elements to reduce layout shifts and improve CLS. Learn how to set image dimensions

Why this matters

Performance issues directly impact user engagement and conversion rates.

URL
Ezra Cornell statue imposed over a red background in front of a large floating … body.home > div#campaign > img#campaignCoverImg
www.cornell.edu/assets/images/campaign/ezra.jpg
div.home-honeycomb > div#honeycomb > a.hc-item > img.image-replace div.home-honeycomb > div#honeycomb > a.hc-item > img.image-replace
/photos/360x360/AB69298D-A62D-B445-9A92E772C3BAD9DD.jpg
div.home-honeycomb > div#honeycomb > a.hc-item > img.image-replace div.home-honeycomb > div#honeycomb > a.hc-item > img.image-replace
/photos/360x360/A746AA91-F77D-AB4C-9F141556580C6E4C.jpg
div.home-honeycomb > div#honeycomb > a.hc-item > img.image-replace div.home-honeycomb > div#honeycomb > a.hc-item > img.image-replace
/photos/360x360/76583D5F-E4A2-0A6C-F49C1FC9E7067410.jpg
div.home-honeycomb > div#honeycomb > a.hc-item > img.image-replace div.home-honeycomb > div#honeycomb > a.hc-item > img.image-replace
/photos/360x360/1A07FF21-BAD7-6A1C-BB7C63EB8210FBE7.jpg
Gavin Sacks. div.slide-mask > div.slideshow > a.grid-box > img.image-replace
/photos/400x225/850FCA14-9FD4-867A-6CD5A1621A680F3E.jpg
Students perform a wet aggregate stability experiment. div.slide-mask > div.slideshow > a.grid-box > img.image-replace
/photos/400x225/4F45AC93-09A5-5E26-B59B80F5D7E369F3.jpg
To do he greatest good: The Campaign for Cornell University li.ftr-item > div.ftr-item-campaign > a > img
media.univcomm.cornell.edu/photos/campaign/TDTGG.png

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 breakdown
●Modern HTTP
●Optimize viewport for mobile
●Max Potential First Input Delay 30 ms
●User Timing marks and measures 5 user timings
●JavaScript execution time 0.1 s
●Minimizes main-thread work 0.7 s
●Page didn't prevent back/forward cache restoration
●Network Requests
●Network Round Trip Times 110 ms
●Server Backend Latencies 110 ms
●Tasks
●Diagnostics
●Metrics
●Screenshot Thumbnails
●Final Screenshot
●Script Treemap Data
●Resources Summary
●Initial server response time was short Root document took 40 ms
●Avoid large layout shifts 3 layout shifts found
○INP breakdown
○Avoid long main-thread tasks
○Avoid non-composited animations
96

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

A value greater than 0 implies an explicit navigation ordering. Although technically valid, this often creates frustrating experiences for users who rely on assistive technologies. Learn more about the `tabindex` attribute.

Why this matters

Performance issues directly impact user engagement and conversion rates.

Failing Elements
Skip to content body.home > nav#skip-link > a
APPLY li.cu-nav-actions > ul > li > a#applyButton
VISIT li.cu-nav-actions > ul > li > a
GIVE li.cu-nav-actions > ul > li > a
STUDENTS li.cu-nav-people > ul > li > a
FAMILIES li.cu-nav-people > ul > li > a
FACULTY & STAFF li.cu-nav-people > ul > li > a
ALUMNI li.cu-nav-people > ul > li > a
div#cu-nav-utility > form.search-main > div.container > input#search-query div#cu-nav-utility > form.search-main > div.container > input#search-query
Search div#cu-nav-utility > form.search-main > div.container > button.icon-search

These are opportunities to improve keyboard navigation in your application.

○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.
●ARIA attributes are used as specified for the element's role
●`[aria-hidden="true"]` elements do not contain focusable descendents
●Elements use only permitted ARIA attributes
●Background and foreground colors have a sufficient contrast ratio
●Document has a `<title>` element
●`<html>` element has a `[lang]` attribute
●`<html>` element has a valid value for its `[lang]` attribute
●Links have a discernible name
●Lists contain only `<li>` elements and script supporting elements (`<script>` and `<template>`).
●List items (`<li>`) are contained within `<ul>`, `<ol>` or `<menu>` parent elements
●Touch targets have sufficient size and spacing.
●Heading elements appear in a sequentially-descending order
●Skip links are focusable.
●Document has a main landmark.
●Deprecated ARIA roles were not used
●`<video>` elements contain a `<track>` element with `[kind="captions"]`
●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
○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.
○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
○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.
77

Best Practices

Trust and Safety

All sites should be protected with HTTPS, even ones that don't handle sensitive data. This includes avoiding mixed content, where some resources are loaded over HTTP despite the initial request being served over HTTPS. HTTPS prevents intruders from tampering with or passively listening in on the communications between your app and your users, and is a prerequisite for HTTP/2 and many new web platform APIs. Learn more about HTTPS.

Why this matters

Performance issues directly impact user engagement and conversion rates.

Insecure URLRequest Resolution
www.cornell.edu/assets/core/social-icons/linkedin-in-logo.svgAutomatically upgraded to HTTPS

General

Issues logged to the `Issues` panel in Chrome Devtools indicate unresolved problems. They can come from network request failures, insufficient security controls, and other browser concerns. Open up the Issues panel in Chrome DevTools for more details on each issue.

Why this matters

Performance issues directly impact user engagement and conversion rates.

Issue type
Mixed content
●Avoids deprecated APIs
●Avoids third-party cookies
●Allows users to paste into input fields
●Avoids requesting the geolocation permission on page load
●Avoids requesting the notification permission on page load
●Displays images with correct aspect ratio
●Serves images with appropriate resolution
●Page has the HTML doctype
●Properly defines charset
●No browser errors logged to the console
●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
●Page has valid source maps
○Redirects HTTP traffic to HTTPS
92

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.

Crawling and Indexing

Search engines may use `href` attributes on links to crawl websites. Ensure that the `href` attribute of anchor elements links to an appropriate destination, so more pages of the site can be discovered. Learn how to make links crawlable

Why this matters

Performance issues directly impact user engagement and conversion rates.

Uncrawlable Link
1 div.container > div.marquee-controls > nav.pager > a.active
2 div.container > div.marquee-controls > nav.pager > a

To appear in search results, crawlers need access to your app.

○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
●robots.txt is valid
●Image elements have `[alt]` attributes
●Document has a valid `hreflang`
○Document has a valid `rel=canonical`

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