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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.

41

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
media.nngroup.com/static/js/output.8221eeaec7a2.js14400.0 s159.3 KiB
connect.facebook.net/en_US/fbevents.js1200.0 s96.6 KiB
media.nngroup.com/media/images/SP_Thumbnails_7_TA3lF90.width-330.png14400.0 s92.6 KiB
media.nngroup.com/media/images/SP_Thumbnails_12_ZXbCnxY.width-330.png14400.0 s84.9 KiB
media.nngroup.com/static/css/output.8a2ac8cc91c7.css14400.0 s77.3 KiB
media.nngroup.com/static/fonts/Inter-VariableFont_opszwght.woff214400.0 s69.3 KiB
/signals/config/1205361211741522?v=2.9.303&r=stable&domai...1200.0 s44.4 KiB
media.nngroup.com/static/img/logos/amazon-logo-home.svg14400.0 s33.9 KiB
media.nngroup.com/static/fonts/SourceSansVariable.subset.min.v4.woff214400.0 s23.6 KiB
media.nngroup.com/static/fonts/SourceSansItalicVariable.subset.min.v4.woff214400.0 s21.0 KiB
media.nngroup.com/static/js/output.3e6a450e0b15.js14400.0 s19.5 KiB
tools.luckyorange.com/core/lo.js?site-id=e5c040f43600.0 s14.3 KiB
media.nngroup.com/static/bundles/consent.js14400.0 s4.6 KiB
media.nngroup.com/media/courses/icons/CourseAI_for_Design_Workflows_0mcAr2s.svg14400.0 s1.6 KiB
cdn-cookieyes.com/assets/images/poweredbtcky.svg36000.0 s1.5 KiB
media.nngroup.com/media/courses/icons/CourseUsability_Testing.svg14400.0 s986 B
media.nngroup.com/static/css/output.e9c610b5facf.css14400.0 s709 B
cdn-cookieyes.com/assets/images/close.svg36000.0 s868 B
/tr/?id=1205361211741522&ev=PageView&dl=https%3A%2F%2Fwww...0.0 ms16 B

Layout shifts occur when elements move absent any user interaction. Investigate the causes of layout shifts, such as elements being added, removed, or their fonts changing as the page loads.

Why this matters

Performance issues directly impact user engagement and conversion rates.

headings: [map[key:node label:Element subItemsHeading:map[key:extra] valueType:node] map[granularity:0.001 key:score label:Layout shift score subItemsHeading:map[key:cause valueType:text] valueType:numeric]]
items: [map[node:map[type:text value:Total] score:0.109408] map[node:map[boundingRect:map[bottom:500 height:410 left:0 right:412 top:90 width:412] lhId:page-1-HEADER nodeLabel:Research-based, results-driven UX guidance and training. Live Online Courses Se… path:1,HTML,1,BODY,6,HEADER selector:body.home > header.banner-image snippet:<header class="banner-image header-rebrand"> type:node] score:0.109318 subItems:map[items:[map[cause:Web font extra:map[type:url value:https://media.nngroup.com/static/fonts/Inter-VariableFont_opszwght.woff2]]] type:subitems]] map[node:map[boundingRect:map[bottom:143 height:45 left:326 right:396 top:98 width:70] lhId:page-3-DIV nodeLabel:Search path:1,HTML,1,BODY,6,HEADER,0,NAV,0,DIV,1,DIV selector:header.banner-image > nav.nav-main > div.ds-wrapper > div.search-and-profile snippet:<div class="search-and-profile"> type:node] score:9e-05]]

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.

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

Why this matters

Performance issues directly impact user engagement and conversion rates.

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

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

Why this matters

Performance issues directly impact user engagement and conversion rates.

URLTransfer SizeDuration
media.nngroup.com/static/css/output.e9c610b5facf.css709 B754 ms
media.nngroup.com/static/css/output.8a2ac8cc91c7.css77.3 KiB601 ms
media.nngroup.com/static/bundles/consent.js4.6 KiB
cdn-cookieyes.com/client_data/1a1cf80aa4378be78f10d807/script.js8.9 KiB806 ms

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: 1.2 s
URLTime Spent
nngroup.com/1.2 s
www.nngroup.com/0.0 ms

These are the largest layout shifts observed on the page. Each table item represents a single layout shift, and shows the element that shifted the most. Below each item are possible root causes that led to the layout shift. Some of these layout shifts may not be included in the CLS metric value due to windowing. Learn how to improve CLS

Why this matters

Performance issues directly impact user engagement and conversion rates.

ElementLayout shift score
Research-based, results-driven UX guidance and training. Live Online Courses Se… body.home > header.banner-image
0.109
Search header.banner-image > nav.nav-main > div.ds-wrapper > div.search-and-profile
0.000

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

Why this matters

Performance issues directly impact user engagement and conversion rates.

TTI

The maximum potential First Input Delay that your users could experience is the duration of the longest task. Learn more about the Maximum Potential First Input Delay metric.

Why this matters

Performance issues directly impact user engagement and conversion rates.

Diagnostics

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: 450 ms 70.4 KiB
URLTransfer SizeEst Savings
media.nngroup.com/static/css/output.8a2ac8cc91c7.css76.9 KiB70.4 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: 910 ms 321.8 KiB
URLTransfer SizeEst Savings
media.nngroup.com/static/js/output.8221eeaec7a2.js158.8 KiB92.1 KiB
www.googletagmanager.com/gtag/js?id=G-630S9ESVKM&cx=c&gtm=4e64h1h1172.7 KiB69.2 KiB
www.googletagmanager.com/gtag/js?id=AW-16569705699&cx=c&gtm=4e64h1h1144.5 KiB65.6 KiB
www.googletagmanager.com/gtm.js?id=GTM-THJDDHK182.7 KiB61.0 KiB
connect.facebook.net/en_US/fbevents.js96.5 KiB33.9 KiB

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

Why this matters

Performance issues directly impact user engagement and conversion rates.

URLTotal CPU TimeScript EvaluationScript Parse
media.nngroup.com/static/js/output.8221eeaec7a2.js752 ms639 ms67 ms
www.nngroup.com/447 ms12 ms2.1 ms
www.googletagmanager.com/gtm.js?id=GTM-THJDDHK405 ms328 ms57 ms
Unattributable366 ms52 ms0.0 ms
www.googletagmanager.com/gtag/js?id=G-630S9ESVKM&cx=c&gtm=4e64h1h1251 ms196 ms42 ms
cdn-cookieyes.com/client_data/1a1cf80aa4378be78f10d807/banner.js243 ms175 ms2.7 ms
www.googletagmanager.com/gtag/js?id=AW-16569705699&cx=c&gtm=4e64h1h1152 ms107 ms40 ms
/signals/config/1205361211741522?v=2.9.303&r=stable&domai...124 ms103 ms14 ms
connect.facebook.net/en_US/fbevents.js122 ms91 ms30 ms
cdn-cookieyes.com/client_data/1a1cf80aa4378be78f10d807/script.js70 ms64 ms1.8 ms

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

Why this matters

Performance issues directly impact user engagement and conversion rates.

CategoryTime Spent
Script Evaluation1.8 s
Other416 ms
Style & Layout342 ms
Script Parsing & Compilation268 ms
Parse HTML & CSS78 ms
Garbage Collection69 ms
Rendering41 ms

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
Amazon Logo div.content > ul > li > img.amazon
media.nngroup.com/static/img/logos/amazon-logo-home.svg

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

●Optimize DOM size
●Font display
●Forced reflow
●Improve image delivery
●LCP breakdown
●Modern HTTP
●Optimize viewport for mobile
●Minify CSS
●Minify JavaScript
●Avoids enormous network payloads Total size was 1,336 KiB
●User Timing marks and measures 5 user timings
●Avoid long main-thread tasks 11 long tasks found
●Page didn't prevent back/forward cache restoration
●Network Requests
●Network Round Trip Times 50 ms
●Server Backend Latencies 380 ms
●Tasks
●Diagnostics
●Metrics
●Screenshot Thumbnails
●Final Screenshot
●Script Treemap Data
●Resources Summary
●Initial server response time was short Root document took 20 ms
○INP breakdown
○LCP request discovery
○Avoid non-composited animations
95

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

Labels ensure that form controls are announced properly by assistive technologies, like screen readers. Learn more about form element labels.

Why this matters

Performance issues directly impact user engagement and conversion rates.

Failing Elements
div.newsletter > form.form-field > div.subscribe-wrap > input.newsletter-email div.newsletter > form.form-field > div.subscribe-wrap > input.newsletter-email

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.

○Interactive controls are keyboard focusable
○Interactive elements indicate their purpose and state
○The page has a logical tab order
○Visual order on the page follows DOM order
○User focus is not accidentally trapped in a region
○The user's focus is directed to new content added to the page
○HTML5 landmark elements are used to improve navigation
○Offscreen content is hidden from assistive technology
○Custom controls have associated labels
○Custom controls have ARIA roles
●`[aria-*]` attributes match their roles
●`[aria-hidden="true"]` is not present on the document `<body>`
●`[role]`s have all required `[aria-*]` attributes
●`[role]` values are valid
●`[aria-*]` attributes have valid values
●`[aria-*]` attributes are valid and not misspelled
●Buttons have an accessible name
●Image elements have `[alt]` attributes
●`[user-scalable="no"]` is not used in the `<meta name="viewport">` element and the `[maximum-scale]` attribute is not less than 5.
●ARIA attributes are used as specified for the element's role
●`[aria-hidden="true"]` elements do not contain focusable descendents
●Elements use only permitted ARIA attributes
●Background and foreground colors have a sufficient contrast ratio
●Document has a `<title>` element
●`<html>` element has a `[lang]` attribute
●`<html>` element has a valid value for its `[lang]` attribute
●Links 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
●Touch targets have sufficient size and spacing.
●Heading elements appear in a sequentially-descending order
●Document has a main landmark.
●Deprecated ARIA roles were not used
●ARIA IDs are unique
●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
○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
○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.
○Identical links have the same purpose.
○Tables use `<caption>` instead of cells with the `[colspan]` attribute to indicate a caption.
○`<td>` elements in a large `<table>` have one or more table headers.
77

Best Practices

General

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

Why this matters

Performance issues directly impact user engagement and conversion rates.

Deprecation / WarningSource
AttributionReporting
connect.facebook.net/en_US/fbevents.js line 279, col 769

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
Content security policy

Source maps translate minified code to the original source code. This helps developers debug in production. In addition, Lighthouse is able to provide further insights. Consider deploying source maps to take advantage of these benefits. Learn more about source maps.

Why this matters

Performance issues directly impact user engagement and conversion rates.

URL
media.nngroup.com/static/js/output.8221eeaec7a2.js
●Uses HTTPS
●Avoids third-party cookies
●Allows users to paste into input fields
●Avoids requesting the geolocation permission on page load
●Avoids requesting the notification permission on page load
●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
●Mitigate DOM-based XSS with Trusted Types
●Detected JavaScript libraries
○Redirects HTTP traffic to HTTPS
○Use a strong HSTS policy
○Ensure proper origin isolation with COOP
○Mitigate clickjacking with XFO or CSP
100

SEO

These checks ensure that your page is following basic search engine optimization advice. There are many additional factors Lighthouse does not score here that may affect your search ranking, including performance on Core Web Vitals. Learn more about Google Search Essentials.

○Structured data is valid
●Page isn’t blocked from indexing
●Document has a `<title>` element
●Document has a meta description
●Page has successful HTTP status code
●Links have descriptive text
●Links are crawlable
●robots.txt is valid
●Image elements have `[alt]` attributes
●Document has a valid `hreflang`
○Document has a valid `rel=canonical`

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