Lighthouse Mobile

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

SCORE

GRADE

FIX

REVIEW

PASS

INFO

Detailed Report

Audit breakdown by category with detailed findings.

Performance

Insights

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

Why this matters

Performance issues directly impact user engagement and conversion rates.

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

Why this matters

Performance issues directly impact user engagement and conversion rates.

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

Why this matters

Performance issues directly impact user engagement and conversion rates.

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

Why this matters

Performance issues directly impact user engagement and conversion rates.

Request	Cache TTL	Transfer Size
/6093eccf-6734-4877-ac8b-83d6d0e27b46-web.js	900.0 s	255.5 KiB
bordeaux.futurecdn.net/bordeaux.js	0.0 ms	159.0 KiB
cdn.privacy-mgmt.com/Notice.8f529.js	3600.0 s	91.2 KiB
cdn.privacy-mgmt.com/unified/wrapperMessagingWithoutDetection.js	3600.0 s	40.4 KiB
freyr.futurecdn.net/freyr.js	0.0 ms	21.1 KiB
scripts.clarity.ms/0.8.59/clarity.js	86400.0 s	26.2 KiB
cdn.privacy-mgmt.com/Notice.30929.css	3600.0 s	6.7 KiB
cse.google.com/cse.js?cx=009882534323254498007:0ejrj_dbalc	0.0 ms	3.6 KiB
sb.scorecardresearch.com/beacon.js	86400.0 s	6.7 KiB
cdn.privacy-mgmt.com/polyfills.01516.js	3600.0 s	2.3 KiB
www.google.com/cse/static/style/look/v6/minimalist.css	3000.0 s	1.3 KiB

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:0.853582] map[score:0.788968] map[score:0.060198] map[node:map[boundingRect:map[bottom:564 height:44 left:94 right:380 top:520 width:286] lhId:page-1-LABEL nodeLabel:Big breakthroughs. Bold ideas. Straight to your inbox. path:1,HTML,1,BODY,10,MAIN,0,DIV,0,DIV,1,DIV,1,DIV,0,SPAN,1,LABEL selector:div.mc-form-wrap > div.beehiiv_embed_signup > span.flex > label.text-h5 snippet:<label class="text-h5 font-source-sans font-semibold text-black ml-3" for="beehiiv-email"> type:node] score:0.004416 subItems:map[items:[map[cause:Web font extra:map[type:url value:https://fonts.gstatic.com/s/sourcesanspro/v23/6xKydSBYKcSV-LCoeQqfX1RYOo3i54rwlxdu3cOWxw.woff2]] map[cause:Web font extra:map[type:url value:https://fonts.gstatic.com/s/opensans/v44/memvYaGs126MiZpBA-UvWbX2vVnXBbObj2OVTS-mu0SC55I.woff2]]] type:subitems]]]

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

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

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
Atomic Clocks Could Reveal The Hidden Quantum Nature of Time Itself `div.container-posts > article#post-198420 > a.flex-shrink-0 > img.w-full`	www.sciencealert.com/images/2026/04/timey-wimey-768x432.jpg	109.4 KiB	103.7 KiB
Curiosity Found Strange 'Dragon Scale' Rocks on Mars, And Scientists Are Excited `div.grid > article#post-198576 > a.flex-shrink-0 > img.w-full`	www.sciencealert.com/images/2026/04/mars-dragonscale-768x432.jpg	69.1 KiB	63.4 KiB
Does Closing Your Eyes Help You Hear? A Surprising Study Has The Answer `div.container-posts > article#post-198114 > a.flex-shrink-0 > img.w-full`	www.sciencealert.com/images/2026/04/listening-768x432.jpg	52.0 KiB	46.3 KiB
A Bolivian Mummy's Tooth Is Rewriting The History of Scarlet Fever `div.container-posts > article#post-198308 > a.flex-shrink-0 > img.w-full`	www.sciencealert.com/images/2026/04/BolivianMummyTooth-768x432.jpg	44.0 KiB	38.6 KiB
Amazonian 'Internet of The Forest' Helps Birds And Monkeys Communicate `div.grid > article#post-198674 > a.flex-shrink-0 > img.w-full`	/images/2026/04/WhiteFronted-Nunbirds-in-the-Amazon-768x4...	43.9 KiB	38.6 KiB
Tinnitus May Be Linked to a Crucial Brain Chemical `div.container-posts > article#post-198545 > a.flex-shrink-0 > img.w-full`	www.sciencealert.com/images/2026/04/WomanHoldsEarInDiscomfort-768x432.jpg	39.0 KiB	34.3 KiB
An abstract human face with eyes closed, morphed with bright colors `div.container-posts > article#post-197961 > a.flex-shrink-0 > img.w-full`	/images/2025/12/Face-Sleeping-Surrounded-by-Color-768x432...	36.5 KiB	32.1 KiB
DNA graphic `div.grid > article#post-198633 > a.flex-shrink-0 > img.w-full`	www.sciencealert.com/images/2026/04/DNAHeader-768x432.jpg	31.0 KiB	27.2 KiB
The Lyrid Meteor Shower Is About to Peak, With Better Views Than Usual `div.container-posts > article#post-198509 > a.flex-shrink-0 > img.w-full`	/images/2026/04/TwoPeopleLyingOnBacksPointingAtNightSky-7...	30.6 KiB	26.9 KiB
Scientists Restore Memory In Aging Mice Using a Simple Nasal Spray `div.container-posts > article#post-198494 > a.flex-shrink-0 > img.w-full`	www.sciencealert.com/images/2026/04/NasalSprayPurpleTonedOnBlack-768x432.jpg	25.9 KiB	22.8 KiB
How Long Poop Stays in Your Body Could Impact Your Health, Study Finds `div.container-posts > article#post-193962 > a.flex-shrink-0 > img.w-full`	www.sciencealert.com/images/2025/10/loo-roll-768x432.jpg	23.2 KiB	20.4 KiB
AI Gives 'Problematic' Health Advice Around Half The Time, Study Suggests `div.container-posts > article#post-198660 > a.flex-shrink-0 > img.w-full`	/images/2026/04/Hands-holding-phone-with-chatbot-on-scree...	22.6 KiB	19.8 KiB
Young Adult Bowel Cancer Deaths Concentrated in One Group, Study Finds `div.container-posts > article#post-198512 > a.flex-shrink-0 > img.w-full`	www.sciencealert.com/images/2026/04/WomanSittingAloneOnHospitalBed-768x432.jpg	21.7 KiB	19.0 KiB
Your Smartwatch May Be Getting 6 Key Health Metrics Wrong `div.container-posts > article#post-198650 > a.flex-shrink-0 > img.w-full`	www.sciencealert.com/images/2026/04/Smartwatch-768x432.jpg	20.6 KiB	18.1 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: 961 ms

URL	Time Spent
sciencealert.com/	961 ms
www.sciencealert.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.

Element	Layout shift score
	0.789
	0.060
Big breakthroughs. Bold ideas. Straight to your inbox. `div.mc-form-wrap > div.beehiiv_embed_signup > span.flex > label.text-h5`	0.004

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: 90 ms 37.2 KiB

URL	Transfer Size	Est Savings
div.story-widget.tbl-reco-reel.tbl-trecs-reco-reel{position:relative} …	13.8 KiB	13.8 KiB
www.google.com/cse/static/element/dc329f57de078f5d/default_v6+en.css	11.9 KiB	11.9 KiB
.trc_rbox_container { direction: ltr; text-align: left; } …	11.5 KiB	11.5 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: 2.8 s 673.4 KiB

URL	Transfer Size	Est Savings
cdn.taboola.com/libtrc/sciencealert/loader.js	323.3 KiB	210.1 KiB
www.googletagmanager.com/gtag/js?id=G-VT6ZH45353&cx=c&gtm=4e64h1	177.8 KiB	114.0 KiB
bordeaux.futurecdn.net/bordeaux.js	158.5 KiB	90.2 KiB
/cse/static/element/dc329f57de078f5d/cse_element__en.js?u...	102.7 KiB	70.3 KiB
www.googletagmanager.com/gtag/js?id=G-VT6ZH45353	177.9 KiB	67.9 KiB
www.googletagmanager.com/gtm.js?id=GTM-T9C3TSJQ	119.8 KiB	62.1 KiB
/6093eccf-6734-4877-ac8b-83d6d0e27b46-web.js	255.0 KiB	37.8 KiB
www.sciencealert.com/wp-includes/js/jquery/jquery.min.js?ver=3.7.1	28.9 KiB	21.0 KiB

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

Why this matters

Performance issues directly impact user engagement and conversion rates.

URL	Total CPU Time	Script Evaluation	Script Parse
www.sciencealert.com/	449 ms	119 ms	11 ms
Unattributable	423 ms	135 ms	0.0 ms
/6093eccf-6734-4877-ac8b-83d6d0e27b46-web.js	351 ms	202 ms	141 ms
cdn.privacy-mgmt.com/unified/4.40.1/usnat-uspapi.090eccada574d39af6f8.bundle.js	267 ms	235 ms	27 ms
cdn.taboola.com/libtrc/sciencealert/loader.js	245 ms	136 ms	109 ms
www.googletagmanager.com/gtag/js?id=G-VT6ZH45353	232 ms	146 ms	42 ms
bordeaux.futurecdn.net/bordeaux.js	226 ms	157 ms	58 ms
scripts.clarity.ms/0.8.59/clarity.js	209 ms	199 ms	6.7 ms
www.googletagmanager.com/gtm.js?id=GTM-T9C3TSJQ	144 ms	105 ms	32 ms
cdn.privacy-mgmt.com/unified/wrapperMessagingWithoutDetection.js	137 ms	107 ms	14 ms
www.googletagmanager.com/gtag/js?id=G-VT6ZH45353&cx=c&gtm=4e64h1	89 ms	51 ms	38 ms
freyr.futurecdn.net/freyr.js	77 ms	68 ms	8.4 ms
www.sciencealert.com/wp-includes/js/jquery/jquery.min.js?ver=3.7.1	73 ms	53 ms	18 ms
cse.google.com/cse.js?cx=009882534323254498007:0ejrj_dbalc	60 ms	47 ms	1.9 ms

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

Why this matters

Performance issues directly impact user engagement and conversion rates.

Category	Time Spent
Script Evaluation	1.9 s
Script Parsing & Compilation	547 ms
Other	393 ms
Style & Layout	217 ms
Parse HTML & CSS	50 ms
Rendering	44 ms
Garbage Collection	42 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 reason	Failure type
The page has an unload handler in the main frame.	Actionable

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 3.3 KiB

URL	Transfer Size	Est Savings
www.google.com/cse/static/element/dc329f57de078f5d/default_v6+en.css	12.0 KiB	3.3 KiB

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

●Optimize DOM size

●Font display

●LCP breakdown

●LCP request discovery

●Modern HTTP

●Render blocking requests

●Optimize viewport for mobile

●Minify JavaScript

●Avoids enormous network payloads Total size was 2,398 KiB

●User Timing marks and measures 14 user timings

●Avoid long main-thread tasks 16 long tasks found

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

●Network Requests

●Network Round Trip Times 100 ms

●Server Backend Latencies 190 ms

●Tasks

●Diagnostics

●Metrics

●Screenshot Thumbnails

●Final Screenshot

●Script Treemap Data

●Resources Summary

●Initial server response time was short Root document took 400 ms

○INP breakdown

○Avoid non-composited animations

100

Accessibility

These checks highlight opportunities to improve the accessibility of your web app. Automatic detection can only detect a subset of issues and does not guarantee the accessibility of your web app, so manual testing is also encouraged.

○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

●Input buttons have discernible text.

●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 have a discernible name

●Touch targets have sufficient size and spacing.

●Document has a main landmark.

●Deprecated ARIA roles were not used

○`[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

○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

○Heading elements appear in a sequentially-descending order

○`<html>` element has an `[xml:lang]` attribute with the same base language as the `[lang]` attribute.

○`<input type="image">` elements have `[alt]` text

○Links are distinguishable without relying on color.

○Lists contain only `<li>` elements and script supporting elements (`<script>` and `<template>`).

○List items (`<li>`) are contained within `<ul>`, `<ol>` or `<menu>` parent elements

○The document does not use `<meta http-equiv="refresh">`

○`<object>` elements have alternate text

○Select elements have associated label elements.

○Skip links are focusable.

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

○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.

○Elements with visible text labels have matching accessible names.

○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

General

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

Why this matters

Performance issues directly impact user engagement and conversion rates.

Deprecation / Warning	Source
Unload event listeners are deprecated and will be removed.	bordeaux.futurecdn.net/bordeaux.js line 31, col 6976

Errors logged to the console indicate unresolved problems. They can come from network request failures and other browser concerns. Learn more about this errors in console diagnostic audit

Why this matters

Performance issues directly impact user engagement and conversion rates.

Source	Description
www.sciencealert.com/.events-handler/future.adtech.freyr.v1.PageViewEvent	`Failed to load resource: the server responded with a status of 403 ()`

●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 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`