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
bridgeslab.sph.umich.edu/lab_website-static/css/custom.css	0.0 ms	267.8 KiB
connect.facebook.net/en_US/bundle/sdk.js/	1200.0 s	78.5 KiB
/v/t39.30808-1/302994671_461759342664757_7704979863435545...	1209600.0 s	53.4 KiB
connect.facebook.net/en_US/sdk.js	1200.0 s	5.0 KiB
bridgeslab.sph.umich.edu/lab_website-static/img/icons/world.png	0.0 ms	3.1 KiB
bridgeslab.sph.umich.edu/lab_website-static/img/icons/user.png	0.0 ms	2.2 KiB
bridgeslab.sph.umich.edu/lab_website-static/img/icons/paste.png	0.0 ms	1.9 KiB
bridgeslab.sph.umich.edu/lab_website-static/img/icons/file.png	0.0 ms	1.7 KiB
bridgeslab.sph.umich.edu/lab_website-static/img/icons/email.png	0.0 ms	1.5 KiB

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

Each subpart has specific improvement strategies. Ideally, most of the LCP time should be spent on loading the resources, not within delays.

Why this matters

Performance issues directly impact user engagement and conversion rates.

headings: [map[key:label label:Subpart valueType:text] map[key:duration label:Duration valueType:ms]]

items: [map[duration:2606.448 label:Time to first byte subpart:timeToFirstByte] map[duration:15.522 label:Resource load delay subpart:resourceLoadDelay] map[duration:454.579 label:Resource load duration subpart:resourceLoadDuration] map[duration:390.619 label:Element render delay subpart:elementRenderDelay]]

lhId: page-0-IMG

nodeLabel: Bridges Lab Photo

path: 1,HTML,1,BODY,2,DIV,0,ARTICLE,1,DIV,0,DIV,0,DIV,0,IMG

selector: div.container > div.row > div.col-sm-3 > img.img-fluid

snippet: <img src="https://scontent-det1-1.xx.fbcdn.net/v/t39.30808-1/302994671_4617593426647…" class="img-fluid" alt="Bridges Lab Photo">

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-IMG

nodeLabel: Bridges Lab Photo

path: 1,HTML,1,BODY,2,DIV,0,ARTICLE,1,DIV,0,DIV,0,DIV,0,IMG

selector: div.container > div.row > div.col-sm-3 > img.img-fluid

snippet: <img src="https://scontent-det1-1.xx.fbcdn.net/v/t39.30808-1/302994671_4617593426647…" class="img-fluid" alt="Bridges Lab Photo">

HTTP/2 and HTTP/3 offer many benefits over HTTP/1.1, such as multiplexing. Learn more about using modern HTTP.

Why this matters

Performance issues directly impact user engagement and conversion rates.

URL	Protocol
bridgeslab.sph.umich.edu/	http/1.1
bridgeslab.sph.umich.edu/lab_website-static/css/custom.css	http/1.1
bridgeslab.sph.umich.edu/lab_website-static/img/icons/user.png	http/1.1
bridgeslab.sph.umich.edu/lab_website-static/img/icons/paste.png	http/1.1
bridgeslab.sph.umich.edu/lab_website-static/img/icons/file.png	http/1.1
bridgeslab.sph.umich.edu/lab_website-static/img/icons/world.png	http/1.1
bridgeslab.sph.umich.edu/lab_website-static/img/icons/email.png	http/1.1

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.

URL	Transfer Size	Duration
bridgeslab.sph.umich.edu/lab_website-static/css/custom.css	267.8 KiB	2.8 s
cdn.jsdelivr.net/npm/bootstrap@5.3.7/dist/js/bootstrap.bundle.min.js	24.3 KiB	300 ms
cdn.jsdelivr.net/npm/bootstrap@5.3.7/dist/css/bootstrap.min.css	33.2 KiB	1.1 s
cdn.jsdelivr.net/npm/bootstrap-icons@1.11.0/font/bootstrap-icons.css	14.1 KiB	150 ms

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
/npm/bootstrap-icons@1.11.0/font/fonts/bootstrap-icons.wo...	10 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.

	URL	Resource Size	Est Savings
Bridges Lab Photo `div.container > div.row > div.col-sm-3 > img.img-fluid`	/v/t39.30808-1/302994671_461759342664757_7704979863435545...	53.4 KiB	20.8 KiB

These insights are also available in the Chrome DevTools Performance Panel - record a trace to view more detailed information.

Keep the server response time for the main document short because all other requests depend on it. Learn more about the Time to First Byte metric.

Why this matters

Performance issues directly impact user engagement and conversion rates.

Estimated savings: 2.0 s

URL	Time Spent
bridgeslab.sph.umich.edu/	2.1 s

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

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: 250 ms 45.1 KiB

URL	Transfer Size	Est Savings
bridgeslab.sph.umich.edu/lab_website-static/css/custom.css	267.8 KiB	45.1 KiB

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: 1.5 s 292.6 KiB

URL	Transfer Size	Est Savings
bridgeslab.sph.umich.edu/lab_website-static/css/custom.css	267.5 KiB	249.1 KiB
cdn.jsdelivr.net/npm/bootstrap@5.3.7/dist/css/bootstrap.min.css	32.4 KiB	30.2 KiB
cdn.jsdelivr.net/npm/bootstrap-icons@1.11.0/font/bootstrap-icons.css	13.3 KiB	13.2 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: 250 ms 117.6 KiB

URL	Transfer Size	Est Savings
www.googletagmanager.com/gtag/js?id=G-HLFFK9ZMJE	145.6 KiB	63.2 KiB
connect.facebook.net/en_US/bundle/sdk.js/	78.3 KiB	54.3 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
Bridges Lab Photo `div.container > div.row > div.col-sm-3 > img.img-fluid`	/v/t39.30808-1/302994671_461759342664757_7704979863435545...
Location `ul#home-links > li > a.text-center > img`	bridgeslab.sph.umich.edu/lab_website-static/img/icons/world.png
People `ul#home-links > li > a.text-center > img`	bridgeslab.sph.umich.edu/lab_website-static/img/icons/user.png
Papers `ul#home-links > li > a.text-center > img`	bridgeslab.sph.umich.edu/lab_website-static/img/icons/file.png
Projects `ul#home-links > li > a.text-center > img`	bridgeslab.sph.umich.edu/lab_website-static/img/icons/paste.png
Contact `ul#home-links > li > a.text-center > img`	bridgeslab.sph.umich.edu/lab_website-static/img/icons/email.png

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

●Layout shift culprits

●Optimize DOM size

●Optimize viewport for mobile

●Minify JavaScript

●Avoids enormous network payloads Total size was 795 KiB

●JavaScript execution time 0.5 s

●Minimizes main-thread work 0.9 s

●Avoid long main-thread tasks 4 long tasks found

●Page didn't prevent back/forward cache restoration

●Network Requests

●Network Round Trip Times 140 ms

●Server Backend Latencies 240 ms

●Tasks

●Diagnostics

●Metrics

●Screenshot Thumbnails

●Final Screenshot

●Script Treemap Data

●Resources Summary

●Avoid multiple page redirects

○INP breakdown

○User Timing marks and measures

○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
2026 Journal Club Articles `div.card > div.card-body > section#2026 > h4.display-8`

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
Amy Zhao, Haijing Sun, Leiyi Yan, Oyewali Shiyanbola, Dave Bridges and Brigid G… `section#recent-papers > div.card > div.card-body > ol.list-unstyled`

Screen readers require list items (`<li>`) to be contained within a parent `<ul>`, `<ol>` or `<menu>` to be announced properly. Learn more about proper list structure.

Why this matters

Performance issues directly impact user engagement and conversion rates.

Failing Elements
Amy Zhao, Haijing Sun, Leiyi Yan, Oyewali Shiyanbola, Dave Bridges and Brigid G… `div.card-body > ol.list-unstyled > div.row > li.border-bottom`
Erwei Li, Yangmian Yuan, Haijing Sun, Khushi Patel, Nan Zhang, Soumya Nagesh, J… `div.card-body > ol.list-unstyled > div.row > li.border-bottom`
Stephanie Eid, Pongrat Jaisil, Kai Guo, John Haynes, Crystal Pacut, Diana Rigan… `div.card-body > ol.list-unstyled > div.row > li.border-bottom`
Treyton Carr, Irit Hochberg and Dave Bridges. Differential Metabolic Signatures… `div.card-body > ol.list-unstyled > div.row > li.border-bottom`
Molly Mulcahy, Noura El Habbal, JeAnna Redd, Haijing Sun, Brigid Gregg and Dave… `div.card-body > ol.list-unstyled > div.row > li.border-bottom`
Brennan AM, Standley RA, Anthony SJ, Grench KE, Helbling NL, DeLany JP, Cornnel… `div.card > div.card-body > section#2026 > li.border-bottom`
Pratap AA, Holsinger RMD. Altered Brain Leptin and Leptin Receptor Expression i… `div.card > div.card-body > section#2026 > li.border-bottom`
Durakoglugil MS, Chen Y, White CL, Kavalali ET, Herz J. Reelin signaling antago… `div.card > div.card-body > section#2026 > li.border-bottom`
O'Sullivan EJ, Perrine CG, Rasmussen KM. Early Breastfeeding Problems Mediate t… `div.card > div.card-body > section#2025 > li.border-bottom`
Horvath D, Mink D, Saxena K, Inholz K, Wirtz PH, Basler M. Stress transmission … `div.card > div.card-body > section#2025 > li.border-bottom`

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

Best practices

One main landmark helps screen reader users navigate a web page. Learn more about landmarks.

Why this matters

Performance issues directly impact user engagement and conversion rates.

Failing Elements
html `html`

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>`

●`[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

●Touch targets have sufficient size and spacing.

●Identical links have the same purpose.

○`[accesskey]` values are unique

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

○Deprecated ARIA roles were not used

○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

○`[role]`s have all required `[aria-*]` attributes

○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

○`[role]` values are valid

○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

○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.

○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.

100

Best Practices

●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 browser errors logged to the console

●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 clickjacking with XFO or CSP

●Mitigate DOM-based XSS with Trusted Types

●Page has valid source maps

○Redirects HTTP traffic to HTTPS

○Detected JavaScript libraries

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

Descriptive link text helps search engines understand your content. Learn how to make links more accessible.

Why this matters

Performance issues directly impact user engagement and conversion rates.

Link destination	Link Text
bridgeslab.sph.umich.edu/papers/	here
bridgeslab.sph.umich.edu/posts/	here
www.facebook.com/	here
bridgeslab.sph.umich.edu/journal-club/	here

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 are crawlable

●robots.txt is valid

●Image elements have `[alt]` attributes

●Document has a valid `hreflang`

○Document has a valid `rel=canonical`