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.

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.

URL	Est Savings
/_assets/4b51f00386267395f41e0940abbcd656/Css/fonts/icomo...	405 ms

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:Top function call valueType:source-location] map[granularity:1 key:reflowTime label:Total reflow time valueType:ms]]

items: [map[reflowTime:4.683 source:map[column:72337 line:13 type:source-location url:https://cdn.jsdelivr.net/npm/swiper@11/swiper-bundle.min.js urlProvider:network]]]

headings: [map[key:source label:Source valueType:source-location] map[granularity:1 key:reflowTime label:Total reflow time valueType:ms]]

items: [map[reflowTime:2.535 source:map[column:4766 line:12 type:source-location url:https://cdn.jsdelivr.net/npm/swiper@11/swiper-bundle.min.js urlProvider:network]] map[reflowTime:0.549 source:map[column:56906 line:12 type:source-location url:https://cdn.jsdelivr.net/npm/swiper@11/swiper-bundle.min.js urlProvider:network]] map[reflowTime:9.237 source:map[column:10640 line:12 type:source-location url:https://cdn.jsdelivr.net/npm/swiper@11/swiper-bundle.min.js urlProvider:network]] map[reflowTime:15.002 source:map[type:text value:[unattributed]]] map[reflowTime:4.007 source:map[column:48353 line:12 type:source-location url:https://cdn.jsdelivr.net/npm/swiper@11/swiper-bundle.min.js urlProvider:network]] map[reflowTime:0.047 source:map[column:22 line:269 type:source-location url:https://www.polimi.it/_assets/4b51f00386267395f41e0940abbcd656/JavaScript/Src/polimi.js?1775796139 urlProvider:network]] map[reflowTime:0.889 source:map[column:31 line:444 type:source-location url:https://www.polimi.it/_assets/4b51f00386267395f41e0940abbcd656/JavaScript/Src/polimi.js?1775796139 urlProvider:network]] map[reflowTime:0.972 source:map[column:180407 line:0 type:source-location url:https://www.polimi.it/_assets/f34691673face4b5c642d176b42916a9/Library/klaro/klaro.js?1765201540 urlProvider:network]]]

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.card-img > figure > picture > img.img-fluid `div.card-img > figure > picture > img.img-fluid`	www.polimi.it/fileadmin/user_upload/news/2026/summer_hp.png	2.7 MiB	2.7 MiB
div.card-img > figure > picture > img.img-fluid `div.card-img > figure > picture > img.img-fluid`	www.polimi.it/fileadmin/user_upload/news/2026/Deploy.png	2.7 MiB	2.7 MiB
div.card-img > figure > picture > img.img-fluid `div.card-img > figure > picture > img.img-fluid`	www.polimi.it/fileadmin/user_upload/news/rettorato/Rettorato_1920x816_v03.jpg	1.5 MiB	1.4 MiB
div.card-img > figure > picture > img.img-fluid `div.card-img > figure > picture > img.img-fluid`	www.polimi.it/fileadmin/user_upload/news/2026/Firma_Polimi-_Autodromo_Monza.jpg	295.8 KiB	263.2 KiB
Eventi 22 aprile 2026 Convegni Convegno Renewable Energy 2026 Leggi 22 apr… `main#page-content > div.section > div.news > div.section--event`	www.polimi.it/_assets/4b51f00386267395f41e0940abbcd656/Images/bgEvents.png	234.7 KiB	120.8 KiB
Build the Future! Scopri il nostro Open Day 2026 Futuri studenti `main#page-content > div.section > div#c18788 > div.banner-cta`	www.polimi.it/_assets/4b51f00386267395f41e0940abbcd656/Images/borealis.jpg	415.6 KiB	78.1 KiB
div.col-12 > div.card > picture.focus-adjust > img.w-100 `div.col-12 > div.card > picture.focus-adjust > img.w-100`	/fileadmin/_processed_/b/7/csm_047-Hero_Sviluppo_Sostenib...	154.7 KiB	77.2 KiB
div.col-12 > div.card > picture.focus-adjust > img.w-100 `div.col-12 > div.card > picture.focus-adjust > img.w-100`	/fileadmin/_processed_/7/d/csm_PolimiSpringGames-200424-9...	138.8 KiB	61.3 KiB
div.col-12 > div.card > picture.focus-adjust > img.w-100 `div.col-12 > div.card > picture.focus-adjust > img.w-100`	/fileadmin/_processed_/d/3/csm_Card_il_Primo_politecnico_...	93.2 KiB	52.8 KiB
div.row > div.col-6 > picture > img.img-fluid `div.row > div.col-6 > picture > img.img-fluid`	www.polimi.it/fileadmin/asset/logo/banner-enhance-logo.png	32.6 KiB	31.1 KiB
Unitech International `div.row > div.col-6 > picture > img.img-fluid`	www.polimi.it/fileadmin/asset/logo/Logo_Unitech.png	30.3 KiB	27.2 KiB
div.row > div.col-6 > picture > img.img-fluid `div.row > div.col-6 > picture > img.img-fluid`	www.polimi.it/fileadmin/asset/logo/banner-time-logo.png	26.6 KiB	24.4 KiB
div.col-12 > div.card > picture.focus-adjust > img.w-100 `div.col-12 > div.card > picture.focus-adjust > img.w-100`	www.polimi.it/fileadmin/_processed_/f/1/csm_test-04_800x600_4f8e0cc7d4.jpg	68.4 KiB	17.1 KiB
Ranking internazionali Un’eccellenza in Italia e nel mondo 1° In Italia 98° … `div.container > div.row > div.col-12 > div.card`	/_assets/4b51f00386267395f41e0940abbcd656/Images/card-gfx...	30.3 KiB	16.8 KiB
div.row > div.col-12 > div.card > ::after `div.row > div.col-12 > div.card > ::after`	/_assets/4b51f00386267395f41e0940abbcd656/Images/card-gfx...	27.5 KiB	14.0 KiB
Collaborazioni Partnership internazionali Orgogliosamente parte di una rete i… `main#page-content > div.section > div#c771 > div.banner-logos`	/_assets/4b51f00386267395f41e0940abbcd656/Images/banner-l...	27.5 KiB	13.2 KiB
div.row > div.col-6 > picture > img.img-fluid `div.row > div.col-6 > picture > img.img-fluid`	www.polimi.it/fileadmin/asset/logo/IDEA_League.png	15.1 KiB	12.9 KiB
div.frame-group-container > div.frame-group-inner > div.frame-backgroundimage-container > div#frame-backgroundimage-c22291 `div.frame-group-container > div.frame-group-inner > div.frame-backgroundimage-container > div#frame-backgroundimage-c22291`	www.polimi.it/fileadmin/_processed_/d/3/csm_banner-cta-background_2a69104123.png	13.5 KiB	9.1 KiB
div#c14813 > div.hero > div.hero__background-image > img#cover-0 `div#c14813 > div.hero > div.hero__background-image > img#cover-0`	www.polimi.it/fileadmin/asset/video/covers/0_technology.jpg	60.9 KiB	6.7 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-18-IMG

nodeLabel: div#c14813 > div.hero > div.hero__background-image > img#cover-0

path: 1,HTML,1,BODY,4,DIV,4,MAIN,1,DIV,0,DIV,2,DIV,4,IMG

selector: div#c14813 > div.hero > div.hero__background-image > img#cover-0

snippet: <img id="cover-0" class="hero__background-image cover current" data-index="0" src="/fileadmin/asset/video/covers/0_technology.jpg" width="1920" height="1080" alt="" style="display: block;">

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.

URL	Transfer Size	Duration
/typo3temp/assets/bootstrappackage/css/theme-8ec6393bb66a...	50.1 KiB	1.2 s
www.polimi.it/_assets/4b51f00386267395f41e0940abbcd656/Css/polimi.css?1775796139	40.2 KiB	611 ms
/_assets/f34691673face4b5c642d176b42916a9/Stylesheet/styl...	5.7 KiB
www.polimi.it/_assets/95f1fea155c1725894ea138b1edbb31d/Scss/corsi.css?1775043311	489 B
/typo3temp/assets/css/e7e212200e72edb6153da3c9aedf7517.cs...	582 B
/_assets/f6ef6adaf5c92bf687a31a3adbcb0f7b/Css/news-basic....	1.2 KiB
unicons.iconscout.com/release/v4.0.8/css/line.css	10.9 KiB	930 ms
cdn.jsdelivr.net/npm/bootstrap@5.3.2/dist/css/bootstrap.min.css	27.6 KiB	1.2 s
cdn.jsdelivr.net/npm/swiper@11/swiper-bundle.min.css	5.1 KiB	152 ms
fonts.googleapis.com/css2?family=Manrope:wght@500;700&display=swap	1.1 KiB	760 ms

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
ingestion.webanalytics.italia.it/matomo.js	86400.0 s	65.6 KiB
cdn.jsdelivr.net/npm/swiper@11/swiper-bundle.min.js	604800.0 s	43.4 KiB
/maze-universal-loader.js?apiKey=e0283946-5145-4bcc-bfbf-...	43200.0 s	2.9 KiB
cdn.jsdelivr.net/npm/swiper@11/swiper-bundle.min.css	604800.0 s	5.1 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: 1.2 s

URL	Time Spent
polimi.it/	1.2 s
www.polimi.it/	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 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: 640 ms 111.0 KiB

URL	Transfer Size	Est Savings
/typo3temp/assets/bootstrappackage/css/theme-8ec6393bb66a...	49.8 KiB	45.8 KiB
www.polimi.it/_assets/4b51f00386267395f41e0940abbcd656/Css/polimi.css?1775796139	39.9 KiB	30.6 KiB
cdn.jsdelivr.net/npm/bootstrap@5.3.2/dist/css/bootstrap.min.css	26.8 KiB	24.4 KiB
unicons.iconscout.com/release/v4.0.8/css/line.css	10.2 KiB	10.2 KiB

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

Why this matters

Performance issues directly impact user engagement and conversion rates.

Estimated savings: 1.8 s 355.9 KiB

URL	Transfer Size	Est Savings
www.googletagmanager.com/gtag/js?id=G-HCPVJRGN8W&cx=c&gtm=4e64k0	172.9 KiB	116.0 KiB
www.googletagmanager.com/gtm.js?id=GTM-TS7S7BXS	148.9 KiB	80.1 KiB
www.googletagmanager.com/gtag/js?id=G-HCPVJRGN8W	172.9 KiB	71.0 KiB
ingestion.webanalytics.italia.it/matomo.js	64.3 KiB	38.2 KiB
cdn.jsdelivr.net/npm/swiper@11/swiper-bundle.min.js	43.1 KiB	28.0 KiB
ajax.googleapis.com/ajax/libs/jquery/3.7.1/jquery.min.js	29.8 KiB	22.6 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
Unattributable	2.3 s	33 ms	0.0 ms
www.polimi.it/	1.3 s	133 ms	18 ms
www.googletagmanager.com/gtag/js?id=G-HCPVJRGN8W	374 ms	297 ms	72 ms
www.googletagmanager.com/gtm.js?id=GTM-TS7S7BXS	265 ms	193 ms	62 ms
/_assets/f34691673face4b5c642d176b42916a9/Library/klaro/k...	240 ms	168 ms	37 ms
/_assets/4b51f00386267395f41e0940abbcd656/JavaScript/Src/...	236 ms	188 ms	3.2 ms
cdn.jsdelivr.net/npm/swiper@11/swiper-bundle.min.js	147 ms	23 ms	20 ms
www.googletagmanager.com/gtag/js?id=G-HCPVJRGN8W&cx=c&gtm=4e64k0	107 ms	34 ms	72 ms
ajax.googleapis.com/ajax/libs/jquery/3.7.1/jquery.min.js	56 ms	42 ms	12 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
Other	2.6 s
Script Evaluation	1.2 s
Style & Layout	708 ms
Script Parsing & Compilation	324 ms
Rendering	230 ms
Parse HTML & CSS	211 ms

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 2.1 KiB

URL	Transfer Size	Est Savings
/_assets/4b51f00386267395f41e0940abbcd656/JavaScript/Src/...	5.3 KiB	2.1 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.

URL	Transfer Size
www.polimi.it/fileadmin/asset/video/3_sostenibilita.mp4	9.0 MiB
www.polimi.it/fileadmin/asset/video/2_didattica.mp4	8.9 MiB
www.polimi.it/fileadmin/asset/video/1_ricerca.mp4	8.7 MiB
www.polimi.it/fileadmin/asset/video/0_technology.mp4	4.8 MiB
www.polimi.it/fileadmin/user_upload/news/2026/summer_hp.png	2.7 MiB
www.polimi.it/fileadmin/user_upload/news/2026/Deploy.png	2.7 MiB
www.polimi.it/fileadmin/user_upload/news/rettorato/Rettorato_1920x816_v03.jpg	1.5 MiB
www.polimi.it/_assets/4b51f00386267395f41e0940abbcd656/Images/borealis.jpg	416.3 KiB
www.polimi.it/fileadmin/asset/video/covers/2_didattica.jpg	380.8 KiB
www.polimi.it/fileadmin/user_upload/news/2026/Firma_Polimi-_Autodromo_Monza.jpg	296.5 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
div.card__variable-flex > div.card-img-wrapper > picture.focus-adjust > img.w-100 `div.card__variable-flex > div.card-img-wrapper > picture.focus-adjust > img.w-100`	/fileadmin/_processed_/c/3/csm__H0A7518_Rettore_650x533_N...
div.row > div.col-6 > picture > img.img-fluid `div.row > div.col-6 > picture > img.img-fluid`	www.polimi.it/fileadmin/asset/logo/banner-enhance-logo.png
Unitech International `div.row > div.col-6 > picture > img.img-fluid`	www.polimi.it/fileadmin/asset/logo/Logo_Unitech.png
div.row > div.col-6 > picture > img.img-fluid `div.row > div.col-6 > picture > img.img-fluid`	www.polimi.it/fileadmin/asset/logo/banner-time-logo.png
div.row > div.col-6 > picture > img.img-fluid `div.row > div.col-6 > picture > img.img-fluid`	www.polimi.it/fileadmin/asset/logo/IDEA_League.png

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

●Layout shift culprits

●Optimize DOM size

●LCP breakdown

●Modern HTTP

●Optimize viewport for mobile

●Minify CSS

●User Timing marks and measures 5 user timings

●Avoid long main-thread tasks 13 long tasks found

●Page didn't prevent back/forward cache restoration

●Network Requests

●Network Round Trip Times 160 ms

●Server Backend Latencies 360 ms

●Tasks

●Diagnostics

●Metrics

●Screenshot Thumbnails

●Final Screenshot

●Script Treemap Data

●Resources Summary

●Initial server response time was short Root document took 180 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
Come funziona l'ammissione `div.card > div.card-img-overlay > div.card-body > h4.card-title`
Entra nella community della prima Università d'Italia `div.contentcontainer > div.contentcontainer-column > div.frame-header > h6.element-header`
Architettura Urbanistica Ingegneria delle Costruzioni `div.col-12 > div.card > div.card-body > h4.card-title`
Raffrescamento sostenibile: lanciata EPIC Deploy `div.card__content > div.card-body > header > h5.card-title`
Convegno Renewable Energy 2026 `div.card__content > div.card-body > header > h6.card-title`
Polimi Community `div.container > div.row > div.col-lg-4 > h4.mb-0`
Sedi `section#footer__accordion > section.footer__headquarters > div#c296 > h6`

These are opportunities to improve keyboard navigation in your application.

Best practices

Touch targets with sufficient size and spacing help users who may have difficulty targeting small controls to activate the targets. Learn more about touch targets.

Why this matters

Performance issues directly impact user engagement and conversion rates.

Failing Elements
IT `section.footer__header > ul#language_menu_footer > li.active > a`

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

●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.

●`button`, `link`, and `menuitem` elements have accessible names

●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

●`<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

●`[lang]` attributes have a valid value

●Skip links are focusable.

●Document has a main landmark.

●Deprecated ARIA roles were not used

●ARIA IDs are unique

●Identical links have the same purpose.

○`[accesskey]` values are unique

○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.

○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.

○`<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.

○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

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.polimi.it/	`AbortError: The play() request was interrupted by a call to pause(). https://goo.gl/LdLk22`

●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

●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

SEO

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

Content Best Practices

hreflang links tell search engines what version of a page they should list in search results for a given language or region. Learn more about `hreflang`.

Why this matters

Performance issues directly impact user engagement and conversion rates.


`head > link`
`head > link`
`head > link`

Canonical links suggest which URL to show in search results. Learn more about canonical links.

Why this matters

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

Source: MDN Permissions-Policy

Format your HTML in a way that enables crawlers to better understand your app’s content.

○Structured data is valid

●Page isn’t blocked from indexing

●Document has a `<title>` element

●Document has a meta description

●Page has successful HTTP status code

●Links have descriptive text

●Links are crawlable

●robots.txt is valid

●Image elements have `[alt]` attributes