Performance and connectivity

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"link_name": "main-menu.support-forum-home", "link_detail": "privacy-and-security" }'> Privacy and security </a> </li> <li> <a href="/en-US/questions/topic/browse" data-event-name="link_click" data-event-parameters='{ "link_name": "main-menu.support-forum-home", "link_detail": "browse" }'> Browse </a> </li> </ul> </section> </div> </div> </div> </div> </li> <li class="mzp-c-menu-category mzp-has-drop-down mzp-js-expandable"> <a class="mzp-c-menu-title sumo-nav--link" href="/en-US/questions/" aria-haspopup="true" aria-controls="mzp-c-menu-panel-help">Ask a Question</a> <div class="mzp-c-menu-panel mzp-has-card" id="mzp-c-menu-panel-help"> <div class="sumo-nav--dropdown-container"> <div class="sumo-nav--dropdown-grid"> <button class="mzp-c-menu-button-close" type="button" aria-controls="mzp-c-menu-panel-example">Close Firefox menu </button> <div class="sumo-nav--dropdown"> <section class="mzp-c-menu-item mzp-has-icon sumo-nav--dropdown-item"> <div class="mzp-c-menu-item-head"> <svg 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"mozilla-account" }'> Mozilla Account </a> </li> <li> <a href="/en-US/questions/new/mobile" data-event-name="link_click" data-event-parameters='{ "link_name": "main-menu.aaq-step-2", "link_detail": "mobile" }'> Firefox for Android </a> </li> <li> <a href="/en-US/questions/new/firefox-private-network-vpn" data-event-name="link_click" data-event-parameters='{ "link_name": "main-menu.aaq-step-2", "link_detail": "firefox-private-network-vpn" }'> Mozilla VPN </a> </li> <li> <a href="/en-US/questions/new/pocket" data-event-name="link_click" data-event-parameters='{ "link_name": "main-menu.aaq-step-2", "link_detail": "pocket" }'> Pocket </a> </li> <li> <a class="color-link" href="/en-US/questions/new" data-event-name="link_click" data-event-parameters='{ "link_name": "main-menu.aaq-step-1", "link_detail": "view-all" }'> View all </a> </li> </ul> </section> </div> </div> </div> </div> </li> <li class="mzp-c-menu-category"> <a class="mzp-c-menu-title sumo-nav--link" href="/en-US/contribute" data-event-name="link_click" data-event-parameters='{"link_name": "main-menu.contribute.contribute-home"}'> Contribute </a> </li> </ul> </nav> </div> </div> <div class="mzp-c-navigation-items sumo-nav--list-wrap-right logged-out" id="profile-navigation"> <div class="mzp-c-navigation-menu"> <nav class="mzp-c-menu mzp-is-basic"> <ul class="mzp-c-menu-category-list sumo-nav--list"> <li class="mzp-c-menu-category sumo-nav--item-right"> <form data-instant-search="form" id="support-search" action="/en-US/search/" method="get" class="simple-search-form"> <input type="hidden" name="product" value="firefox" /> <input spellcheck="true" type="search" autocomplete="off" name="q" aria-required="true" placeholder="Search questions, articles, or topics (example: saving passwords in Firefox)" class="searchbox" id="search-q" /> <button type="submit" title="Search" class="search-button">Search</button> </form> </li> <li class="mzp-c-menu-category logged-out-button-row "> <a rel="nofollow" href="/en-US/users/auth" class="sumo-button secondary-button button-lg" data-event-name="link_click" data-event-parameters='{"link_name": "main-menu.sign-in-up"}'> Sign In/Up </a> </li> </ul> </nav> </div> </div> <div class="mzp-c-navigation-items sumo-nav--mobile-search-form" id="search-navigation"> <div class="mzp-c-navigation-menu"> <nav class="mzp-c-menu mzp-is-basic"> <form data-instant-search="form" id="mobile-search-results" action="/en-US/search/" method="get" class="simple-search-form"> <input type="hidden" name="product" value="firefox" /> <input spellcheck="true" type="search" autocomplete="off" name="q" aria-required="true" placeholder="Search questions, articles, or topics (example: saving passwords in Firefox)" class="searchbox" id="search-q" /> <button type="submit" title="Search" class="search-button">Search</button> </form> </nav> </div> </div> </div> </div> </header>  <div class="home-search-section sumo-page-section--lg shade-bg hidden-search-masthead"> <div class="mzp-l-content narrow"> <div class="home-search-section--content"> <h4 class="sumo-page-heading-xl">Search Support</h4> <form data-instant-search="form" id="hidden-search" action="/en-US/search/" method="get" class="simple-search-form"> <input type="hidden" name="product" value="firefox" /> <input spellcheck="true" type="search" autocomplete="off" name="q" aria-required="true" placeholder="Search questions, articles, or topics (example: saving passwords in Firefox)" class="searchbox" id="search-q" /> <button type="submit" title="Search" class="search-button">Search</button> </form> </div> </div> </div> <div class="mzp-l-content " id="main-content"> <div class="sumo-page-section--inner"> <div class="breadcrumbs" id="main-breadcrumbs"> <ol id="breadcrumbs" class="breadcrumbs--list"> <li><a href="/en-US/">Home</a></li> <li><a href="/en-US/products/firefox">Firefox</a></li> <li>Performance and connectivity</li> </ol> </div> <div class="sumo-l-two-col "> <aside id="aside" class="sumo-l-two-col--sidebar"> <div class="search-form-sidebar large-only"> <form data-instant-search="form" id="support-search-sidebar" action="/en-US/search/" method="get" class="simple-search-form"> <input type="hidden" name="product" value="firefox" /> <input spellcheck="true" type="search" autocomplete="off" name="q" aria-required="true" placeholder="Search questions, articles, or topics (example: saving passwords in Firefox)" class="searchbox" id="search-q" /> <button type="submit" title="Search" class="search-button">Search</button> </form> </div> <h3 class="sidebar-subheading large-only">Popular Firefox Topics</h3> <nav class="sidebar-nav topics"> <span class="details-heading"></span> <ul class="sidebar-nav--list"> <li class="sidebar-nav--item has-subtopics "> <a class=" sidebar-nav--link " href="/en-US/products/firefox/backup-recovery-and-sync" data-event-name="link_click" data-event-parameters='{ "link_name": "sidebar.product-and-topic-home", "link_detail": "firefox/backup-recovery-and-sync" }'> Backup, recovery, and sync </a> </li> <li class="sidebar-nav--item has-subtopics "> <a class=" sidebar-nav--link " href="/en-US/products/firefox/browse" data-event-name="link_click" data-event-parameters='{ "link_name": "sidebar.product-and-topic-home", "link_detail": "firefox/browse" }'> Browse </a> </li> <li class="sidebar-nav--item has-subtopics "> <a class=" sidebar-nav--link selected " href="/en-US/products/firefox/performance-and-connectivity" data-event-name="link_click" data-event-parameters='{ "link_name": "sidebar.product-and-topic-home", "link_detail": "firefox/performance-and-connectivity" }'> Performance and connectivity </a> <ul class="sidebar-nav--sublist"> <li class="sidebar-nav--subitem"> <a class="sidebar-nav--sublink " href="/en-US/products/firefox/performance-and-connectivity/crashing-and-slow-performance" data-event-name="link_click" data-event-parameters='{ "link_name": "sidebar.product-and-topic-and-subtopic-home", "link_detail": "firefox/performance-and-connectivity/crashing-and-slow-performance" }'> Crashing and slow performance </a> </li> <li class="sidebar-nav--subitem"> <a class="sidebar-nav--sublink " href="/en-US/products/firefox/performance-and-connectivity/site-breakages" data-event-name="link_click" data-event-parameters='{ "link_name": "sidebar.product-and-topic-and-subtopic-home", "link_detail": "firefox/performance-and-connectivity/site-breakages" }'> Site breakages </a> </li> <li class="sidebar-nav--subitem"> <a class="sidebar-nav--sublink " href="/en-US/products/firefox/performance-and-connectivity/connectivity" data-event-name="link_click" data-event-parameters='{ "link_name": "sidebar.product-and-topic-and-subtopic-home", "link_detail": "firefox/performance-and-connectivity/connectivity" }'> Connectivity </a> </li> <li class="sidebar-nav--subitem"> <a class="sidebar-nav--sublink " href="/en-US/products/firefox/performance-and-connectivity/error-codes" data-event-name="link_click" data-event-parameters='{ "link_name": "sidebar.product-and-topic-and-subtopic-home", "link_detail": "firefox/performance-and-connectivity/error-codes" }'> Error codes </a> </li> </ul> </li> <li class="sidebar-nav--item has-subtopics "> <a class=" sidebar-nav--link " href="/en-US/products/firefox/accessibility" data-event-name="link_click" data-event-parameters='{ "link_name": "sidebar.product-and-topic-home", "link_detail": "firefox/accessibility" }'> Accessibility </a> </li> <li class="sidebar-nav--item has-subtopics "> <a class=" sidebar-nav--link " href="/en-US/products/firefox/download-and-save" data-event-name="link_click" data-event-parameters='{ "link_name": "sidebar.product-and-topic-home", "link_detail": "firefox/download-and-save" }'> Download and save </a> </li> <li class="sidebar-nav--item has-subtopics "> <a class=" sidebar-nav--link " href="/en-US/products/firefox/search-tag-and-share" data-event-name="link_click" data-event-parameters='{ "link_name": "sidebar.product-and-topic-home", "link_detail": "firefox/search-tag-and-share" }'> Search, tag, and share </a> </li> <li class="sidebar-nav--item has-subtopics "> <a class=" sidebar-nav--link " href="/en-US/products/firefox/installation-and-updates" data-event-name="link_click" data-event-parameters='{ "link_name": "sidebar.product-and-topic-home", "link_detail": "firefox/installation-and-updates" }'> Installation and updates </a> </li> <li class="sidebar-nav--item has-subtopics "> <a class=" sidebar-nav--link " href="/en-US/products/firefox/settings" data-event-name="link_click" data-event-parameters='{ "link_name": "sidebar.product-and-topic-home", "link_detail": "firefox/settings" }'> Settings </a> </li> <li class="sidebar-nav--item has-subtopics "> <a class=" sidebar-nav--link " href="/en-US/products/firefox/privacy-and-security" data-event-name="link_click" data-event-parameters='{ "link_name": "sidebar.product-and-topic-home", "link_detail": "firefox/privacy-and-security" }'> Privacy and security </a> </li> <li class="sidebar-nav--item has-subtopics "> <a class=" sidebar-nav--link " href="/en-US/products/firefox/passwords-and-sign-in" data-event-name="link_click" data-event-parameters='{ "link_name": "sidebar.product-and-topic-home", "link_detail": "firefox/passwords-and-sign-in" }'> Passwords and sign in </a> </li> </ul> </nav> <div class="aaq-widget card is-inverse elevation-01 text-center radius-md"> <h2 class="card--title has-bottom-margin"> <svg class="card--icon-sm" width="24px" height="24px" viewBox="0 0 24 24" xmlns="http://www.w3.org/2000/svg"> <g stroke="none" stroke-width="1" fill="none" fill-rule="evenodd" stroke-linecap="round" stroke-linejoin="round"> <g transform="translate(2.000000, 1.878680)" stroke="#FFFFFF" stroke-width="2"> <path d="M9,1.12132031 L2,1.12132031 C0.8954305,1.12132031 5.32907052e-15,2.01675081 5.32907052e-15,3.12132031 L5.32907052e-15,15.1213203 C5.32907052e-15,16.2258898 0.8954305,17.1213203 2,17.1213203 L11,17.1213203 L13,21.1213203 L15,17.1213203 L17,17.1213203 C18.1045695,17.1213203 19,16.2258898 19,15.1213203 L19,9.12132031"></path> <path d="M15.5,0.621320312 C16.3284271,-0.207106783 17.6715729,-0.207106769 18.5,0.621320344 C19.3284271,1.44974746 19.3284271,2.79289318 18.5,3.62132031 L11,11.1213203 L7,12.1213203 L8,8.12132031 L15.5,0.621320312 Z"></path> </g> </g> </svg> Ask a Question </h2> <p>Still need help? Sign in to ask your question on our forums.</p> <a class="sumo-button primary-button feature-box" href="/en-US/questions/new/firefox/form" data-event-name="link_click" data-event-parameters='{ "link_name": "aaq-widget.aaq-step-3", "link_detail": "firefox" }'> Continue </a> </div> </aside> <main role="main" class="sumo-l-two-col--main"> <article id="document-list"> <header class="sumo-article-header"> <div class="sumo-article-header--text"> <div class="documents-product-title"> <a href="/en-US/products/firefox"><img src="https://assets-prod.sumo.prod.webservices.mozgcp.net/media/uploads/products/2020-04-14-08-36-13-8dda6f.png" height="48" width="48" alt="" /></a> <div class="firefox-download-button hidden"> <div class="download-buttons"> <div class="download-firefox"> <a href="https://www.mozilla.org/firefox/new/?utm_source=support.mozilla.org&utm_medium=referral&utm_campaign=non-fx-button&utm_content=body-download-button" class="download-button sumo-button primary-button button-lg"> Download Firefox </a> <ul class="download-info text-body-xs"> <li><a href="https://www.mozilla.org/firefox/all/">Systems and Languages</a></li> <li><a href="https://www.mozilla.org/firefox/notes">What's New</a></li> <li><a href="https://www.mozilla.org/legal/privacy/firefox">Privacy</a></li> </ul> </div> </div> </div> </div> <h1 class="topic-title sumo-page-heading"> Performance and connectivity </h1> <p class="topic-description sumo-page-intro mb-0"> Deal with error messages, crashing applications, connectivity issues, and slow performance. </p> </div> </header> <nav class="tabs"> <ul class="tabs--list subtopics"> <li class="tabs--item"> <a class="tabs--link is-active" href="/en-US/products/firefox/performance-and-connectivity" data-event-name="link_click" data-event-parameters='{ "link_name": "tab.product-and-topic-home", "link_detail": "firefox/performance-and-connectivity" }'> <span class="mobile-only">All</span> <span class="hide-on-mobile">All articles and threads</span> </a> </li> <li class="tabs--item"> <a class="tabs--link " href="/en-US/products/firefox/performance-and-connectivity/crashing-and-slow-performance" data-event-name="link_click" data-event-parameters='{ "link_name": "tab.product-and-topic-and-subtopic-home", "link_detail": "firefox/performance-and-connectivity/crashing-and-slow-performance" }'> <span>Crashing and slow performance</span> </a> </li> <li class="tabs--item"> <a class="tabs--link " href="/en-US/products/firefox/performance-and-connectivity/site-breakages" data-event-name="link_click" data-event-parameters='{ "link_name": "tab.product-and-topic-and-subtopic-home", "link_detail": "firefox/performance-and-connectivity/site-breakages" }'> <span>Site breakages</span> </a> </li> <li class="tabs--item"> <a class="tabs--link " href="/en-US/products/firefox/performance-and-connectivity/connectivity" data-event-name="link_click" data-event-parameters='{ "link_name": "tab.product-and-topic-and-subtopic-home", "link_detail": "firefox/performance-and-connectivity/connectivity" }'> <span>Connectivity</span> </a> </li> <li class="tabs--item"> <a class="tabs--link " href="/en-US/products/firefox/performance-and-connectivity/error-codes" data-event-name="link_click" data-event-parameters='{ "link_name": "tab.product-and-topic-and-subtopic-home", "link_detail": "firefox/performance-and-connectivity/error-codes" }'> <span>Error codes</span> </a> </li> </ul> </nav> <section class="topic-list"> <article class="topic-article no-bottom-margin"> <div class="topic-article--icon-wrap"> <img class="topic-article--icon" src="https://assets-prod.sumo.prod.webservices.mozgcp.net/static/reader-mode.1d40422a5274c27c.svg" alt="" /> </div> <div class="topic-article--text"> <h2 class="sumo-card-heading"> <a href="/en-US/kb/troubleshoot-time-errors-secure-websites" data-event-name="link_click" data-event-parameters='{"link_name": "kb-article"}'> How to troubleshoot time related errors on secure websites </a> </h2> <p>Learn why you might see time-related errors on HTTPS websites and how you can troubleshoot these errors by correcting your system clock.</p> <div id="document_metadata" class="has-border-top"> <span class="product tooltip-container"> Firefox <span class="tooltip">Firefox</span> </span> <span class="last-updated"> <img class="pencil" src="https://assets-prod.sumo.prod.webservices.mozgcp.net/static/pencil.e33c563f24c4f989.svg" /> <strong>Last updated:</strong> <span class="time"> <time datetime="2024-03-21T12:33:40.332866-07:00">3/21/24</time> </span> </span> </div> </div> </article> <article class="topic-article no-bottom-margin"> <div class="topic-article--icon-wrap"> <img class="topic-article--icon" src="https://assets-prod.sumo.prod.webservices.mozgcp.net/static/reader-mode.1d40422a5274c27c.svg" alt="" /> </div> <div class="topic-article--text"> <h2 class="sumo-card-heading"> <a href="/en-US/kb/xframe-neterror-page" data-event-name="link_click" data-event-parameters='{"link_name": "kb-article"}'> Website will not allow Firefox to display the page if another site has embedded it </a> </h2> <p>This page explains the error: "Website will not allow Firefox to display the page if another site has embedded it"</p> <div id="document_metadata" class="has-border-top"> <span class="product tooltip-container"> Firefox, Firefox for Android <span class="tooltip">Firefox, Firefox for Android</span> </span> <span class="last-updated"> <img class="pencil" src="https://assets-prod.sumo.prod.webservices.mozgcp.net/static/pencil.e33c563f24c4f989.svg" /> <strong>Last updated:</strong> <span class="time"> <time datetime="2024-12-24T13:51:43.560883-08:00">12/24/24</time> </span> </span> </div> </div> </article> <article class="topic-article no-bottom-margin"> <div class="topic-article--icon-wrap"> <img class="topic-article--icon" src="https://assets-prod.sumo.prod.webservices.mozgcp.net/static/reader-mode.1d40422a5274c27c.svg" alt="" /> </div> <div class="topic-article--text"> <h2 class="sumo-card-heading"> <a href="/en-US/kb/captive-portal" data-event-name="link_click" data-event-parameters='{"link_name": "kb-article"}'> Captive portal detection </a> </h2> <p>Description of how Firefox detects captive portal networks.</p> <div id="document_metadata" class="has-border-top"> <span class="product tooltip-container"> Firefox <span class="tooltip">Firefox</span> </span> <span class="last-updated"> <img class="pencil" src="https://assets-prod.sumo.prod.webservices.mozgcp.net/static/pencil.e33c563f24c4f989.svg" /> <strong>Last updated:</strong> <span class="time"> <time datetime="2024-10-11T06:50:17.491248-07:00">10/11/24</time> </span> </span> </div> </div> </article> <article class="topic-article no-bottom-margin"> <div class="topic-article--icon-wrap"> <img class="topic-article--icon" src="https://assets-prod.sumo.prod.webservices.mozgcp.net/static/reader-mode.1d40422a5274c27c.svg" alt="" /> </div> <div class="topic-article--text"> <h2 class="sumo-card-heading"> <a href="/en-US/kb/connection-settings-firefox" data-event-name="link_click" data-event-parameters='{"link_name": "kb-article"}'> Connection settings in Firefox </a> </h2> <p>Your organization or Internet Service Provider may offer or require you to use a proxy to connect to the Internet. Learn more.</p> <div id="document_metadata" class="has-border-top"> <span class="product tooltip-container"> Firefox <span class="tooltip">Firefox</span> </span> <span class="last-updated"> <img class="pencil" src="https://assets-prod.sumo.prod.webservices.mozgcp.net/static/pencil.e33c563f24c4f989.svg" /> <strong>Last updated:</strong> <span class="time"> <time datetime="2024-12-16T10:14:40.406854-08:00">12/16/24</time> </span> </span> </div> </div> </article> <article class="topic-article no-bottom-margin"> <div class="topic-article--icon-wrap"> <img class="topic-article--icon" src="https://assets-prod.sumo.prod.webservices.mozgcp.net/static/reader-mode.1d40422a5274c27c.svg" alt="" /> </div> <div class="topic-article--text"> <h2 class="sumo-card-heading"> <a href="/en-US/kb/error-codes-secure-websites" data-event-name="link_click" data-event-parameters='{"link_name": "kb-article"}'> How to troubleshoot security error codes on secure websites </a> </h2> <p>Learn about the error codes SEC_ERROR_UNKNOWN_ISSUER MOZILLA_PKIX_ERROR_MITM_DETECTED and ERROR_SELF_SIGNED_CERT on HTTPS websites and how to troubleshoot.</p> <div id="document_metadata" class="has-border-top"> <span class="product tooltip-container"> Firefox <span class="tooltip">Firefox</span> </span> <span class="last-updated"> <img class="pencil" src="https://assets-prod.sumo.prod.webservices.mozgcp.net/static/pencil.e33c563f24c4f989.svg" /> <strong>Last updated:</strong> <span class="time"> <time datetime="2023-07-27T22:12:32-07:00">7/27/23</time> </span> </span> </div> </div> </article> <article class="topic-article no-bottom-margin"> <div class="topic-article--icon-wrap"> <img class="topic-article--icon" src="https://assets-prod.sumo.prod.webservices.mozgcp.net/static/reader-mode.1d40422a5274c27c.svg" alt="" /> </div> <div class="topic-article--text"> <h2 class="sumo-card-heading"> <a href="/en-US/kb/diagnose-firefox-issues-using-troubleshoot-mode" data-event-name="link_click" data-event-parameters='{"link_name": "kb-article"}'> Diagnose Firefox issues using Troubleshoot Mode </a> </h2> <p>Use Firefox Troubleshoot Mode (known as Safe Mode in previous versions of Firefox) to diagnose and fix problems. Learn more.</p> <div id="document_metadata" class="has-border-top"> <span class="product tooltip-container"> Firefox <span class="tooltip">Firefox</span> </span> <span class="last-updated"> <img class="pencil" src="https://assets-prod.sumo.prod.webservices.mozgcp.net/static/pencil.e33c563f24c4f989.svg" /> <strong>Last updated:</strong> <span class="time"> <time datetime="2023-03-13T02:00:55-07:00">3/13/23</time> </span> </span> </div> </div> </article> <article class="topic-article no-bottom-margin"> <div class="topic-article--icon-wrap"> <img class="topic-article--icon" src="https://assets-prod.sumo.prod.webservices.mozgcp.net/static/reader-mode.1d40422a5274c27c.svg" alt="" /> </div> <div class="topic-article--text"> <h2 class="sumo-card-heading"> <a href="/en-US/kb/what-does-your-connection-is-not-secure-mean" data-event-name="link_click" data-event-parameters='{"link_name": "kb-article"}'> What do the security warning codes mean? </a> </h2> <p>Firefox shows you a warning page about a potential security risk when you try to connect to a secure site but your connection is not secure.</p> <div id="document_metadata" class="has-border-top"> <span class="product tooltip-container"> Firefox <span class="tooltip">Firefox</span> </span> <span class="last-updated"> <img class="pencil" src="https://assets-prod.sumo.prod.webservices.mozgcp.net/static/pencil.e33c563f24c4f989.svg" /> <strong>Last updated:</strong> <span class="time"> <time datetime="2023-09-11T15:05:10-07:00">9/11/23</time> </span> </span> </div> </div> </article> <article class="topic-article no-bottom-margin"> <div class="topic-article--icon-wrap"> <img class="topic-article--icon" src="https://assets-prod.sumo.prod.webservices.mozgcp.net/static/reader-mode.1d40422a5274c27c.svg" alt="" /> </div> <div class="topic-article--text"> <h2 class="sumo-card-heading"> <a href="/en-US/kb/troubleshoot-and-diagnose-firefox-problems" data-event-name="link_click" data-event-parameters='{"link_name": "kb-article"}'> Troubleshoot and diagnose Firefox problems </a> </h2> <p>This article includes a series of steps you can follow, that will help you fix most problems with Firefox.</p> <div id="document_metadata" class="has-border-top"> <span class="product tooltip-container"> Firefox <span class="tooltip">Firefox</span> </span> <span class="last-updated"> <img class="pencil" src="https://assets-prod.sumo.prod.webservices.mozgcp.net/static/pencil.e33c563f24c4f989.svg" /> <strong>Last updated:</strong> <span class="time"> <time datetime="2024-07-30T12:54:52.964197-07:00">7/30/24</time> </span> </span> </div> </div> </article> <article class="topic-article no-bottom-margin"> <div class="topic-article--icon-wrap"> <img class="topic-article--icon" src="https://assets-prod.sumo.prod.webservices.mozgcp.net/static/reader-mode.1d40422a5274c27c.svg" alt="" /> </div> <div class="topic-article--text"> <h2 class="sumo-card-heading"> <a href="/en-US/kb/firefox-cant-load-websites-other-browsers-can" data-event-name="link_click" data-event-parameters='{"link_name": "kb-article"}'> Firefox can't load websites but other browsers can </a> </h2> <p>We'll explain errors such as "Server not found" or "Unable to connect" and how to fix problems where Firefox can't access websites but other browsers can.</p> <div id="document_metadata" class="has-border-top"> <span class="product tooltip-container"> Firefox <span class="tooltip">Firefox</span> </span> <span class="last-updated"> <img class="pencil" src="https://assets-prod.sumo.prod.webservices.mozgcp.net/static/pencil.e33c563f24c4f989.svg" /> <strong>Last updated:</strong> <span class="time"> <time datetime="2022-07-07T18:26:36-07:00">7/7/22</time> </span> </span> </div> </div> </article> <article class="topic-article no-bottom-margin"> <div class="topic-article--icon-wrap"> <img class="topic-article--icon" src="https://assets-prod.sumo.prod.webservices.mozgcp.net/static/reader-mode.1d40422a5274c27c.svg" alt="" /> </div> <div class="topic-article--text"> <h2 class="sumo-card-heading"> <a href="/en-US/kb/dns-over-https-doh-faqs" data-event-name="link_click" data-event-parameters='{"link_name": "kb-article"}'> DNS over HTTPS (DoH) FAQs </a> </h2> <p>We have outlined a list of FAQs here that you may find helpful while getting up to speed with all that DNS over HTTPS (DoH) has to offer.</p> <div id="document_metadata" class="has-border-top"> <span class="product tooltip-container"> Firefox <span class="tooltip">Firefox</span> </span> <span class="last-updated"> <img class="pencil" src="https://assets-prod.sumo.prod.webservices.mozgcp.net/static/pencil.e33c563f24c4f989.svg" /> <strong>Last updated:</strong> <span class="time"> <time datetime="2024-12-02T05:51:04.083134-08:00">12/2/24</time> </span> </span> </div> </div> </article> <article class="topic-article no-bottom-margin"> <div class="topic-article--icon-wrap"> <img class="topic-article--icon" src="https://assets-prod.sumo.prod.webservices.mozgcp.net/static/reader-mode.1d40422a5274c27c.svg" alt="" /> </div> <div class="topic-article--text"> <h2 class="sumo-card-heading"> <a href="/en-US/kb/report-breakage-due-blocking" data-event-name="link_click" data-event-parameters='{"link_name": "kb-article"}'> How do I report a broken site in Firefox desktop? </a> </h2> <p>How to report a broken website and what information Mozilla receives when you report breakage caused by Enhanced Tracking Protection.</p> <div id="document_metadata" class="has-border-top"> <span class="product tooltip-container"> Firefox <span class="tooltip">Firefox</span> </span> <span class="last-updated"> <img class="pencil" src="https://assets-prod.sumo.prod.webservices.mozgcp.net/static/pencil.e33c563f24c4f989.svg" /> <strong>Last updated:</strong> <span class="time"> <time datetime="2024-02-22T11:48:18.925425-08:00">2/22/24</time> </span> </span> </div> </div> </article> <article class="topic-article no-bottom-margin"> <div class="topic-article--icon-wrap"> <img class="topic-article--icon" src="https://assets-prod.sumo.prod.webservices.mozgcp.net/static/reader-mode.1d40422a5274c27c.svg" alt="" /> </div> <div class="topic-article--text"> <h2 class="sumo-card-heading"> <a href="/en-US/kb/resist-fingerprinting" data-event-name="link_click" data-event-parameters='{"link_name": "kb-article"}'> Resist Fingerprinting </a> </h2> <p>Firefox's Advanced Preferences to resist fingerprinting can help prevent websites from uniquely identifying your device but can cause problems. Learn more.</p> <div id="document_metadata" class="has-border-top"> <span class="product tooltip-container"> Firefox <span class="tooltip">Firefox</span> </span> <span class="last-updated"> <img class="pencil" src="https://assets-prod.sumo.prod.webservices.mozgcp.net/static/pencil.e33c563f24c4f989.svg" /> <strong>Last updated:</strong> <span class="time"> <time datetime="2025-01-07T13:32:27.306583-08:00">1/7/25</time> </span> </span> </div> </div> </article> <article class="topic-article no-bottom-margin"> <div class="topic-article--icon-wrap"> <img class="topic-article--icon" src="https://assets-prod.sumo.prod.webservices.mozgcp.net/static/reader-mode.1d40422a5274c27c.svg" alt="" /> </div> <div class="topic-article--text"> <h2 class="sumo-card-heading"> <a href="/en-US/kb/configure-windows-firewall-allow-firefox-access" data-event-name="link_click" data-event-parameters='{"link_name": "kb-article"}'> How to let Firefox use the internet on your Windows computer </a> </h2> <p>A "Server not found" error can be caused by Windows Firewall blocking Firefox from accessing the Internet. Learn how to configure it to allow Firefox access.</p> <div id="document_metadata" class="has-border-top"> <span class="product tooltip-container"> Firefox <span class="tooltip">Firefox</span> </span> <span class="last-updated"> <img class="pencil" src="https://assets-prod.sumo.prod.webservices.mozgcp.net/static/pencil.e33c563f24c4f989.svg" /> <strong>Last updated:</strong> <span class="time"> <time datetime="2022-02-19T20:29:24-08:00">2/19/22</time> </span> </span> </div> </div> </article> <article class="topic-article no-bottom-margin"> <div class="topic-article--icon-wrap"> <img class="topic-article--icon" src="https://assets-prod.sumo.prod.webservices.mozgcp.net/static/reader-mode.1d40422a5274c27c.svg" alt="" /> </div> <div class="topic-article--text"> <h2 class="sumo-card-heading"> <a href="/en-US/kb/use-troubleshooting-information-page-fix-firefox" data-event-name="link_click" data-event-parameters='{"link_name": "kb-article"}'> Use the Troubleshooting Information page to help fix Firefox issues </a> </h2> <p>The Troubleshooting Information page has tools and details about your Firefox installation, that can help you solve problems with Firefox.</p> <div id="document_metadata" class="has-border-top"> <span class="product tooltip-container"> Firefox <span class="tooltip">Firefox</span> </span> <span class="last-updated"> <img class="pencil" src="https://assets-prod.sumo.prod.webservices.mozgcp.net/static/pencil.e33c563f24c4f989.svg" /> <strong>Last updated:</strong> <span class="time"> <time datetime="2024-12-08T09:10:20.818253-08:00">12/8/24</time> </span> </span> </div> </div> </article> <article class="topic-article no-bottom-margin"> <div class="topic-article--icon-wrap"> <img class="topic-article--icon" src="https://assets-prod.sumo.prod.webservices.mozgcp.net/static/reader-mode.1d40422a5274c27c.svg" alt="" /> </div> <div class="topic-article--text"> <h2 class="sumo-card-heading"> <a href="/en-US/kb/firefox-dns-over-https" data-event-name="link_click" data-event-parameters='{"link_name": "kb-article"}'> Firefox DNS over HTTPS </a> </h2> <p>DoH improves privacy by hiding domain name lookups from anyone lurking on public Wi-Fi, your ISP or others on your local network. Learn more.</p> <div id="document_metadata" class="has-border-top"> <span class="product tooltip-container"> Firefox <span class="tooltip">Firefox</span> </span> <span class="last-updated"> <img class="pencil" src="https://assets-prod.sumo.prod.webservices.mozgcp.net/static/pencil.e33c563f24c4f989.svg" /> <strong>Last updated:</strong> <span class="time"> <time datetime="2024-12-02T05:48:46.090580-08:00">12/2/24</time> </span> </span> </div> </div> </article> <article class="topic-article no-bottom-margin"> <div class="topic-article--icon-wrap"> <img class="topic-article--icon" src="https://assets-prod.sumo.prod.webservices.mozgcp.net/static/reader-mode.1d40422a5274c27c.svg" alt="" /> </div> <div class="topic-article--text"> <h2 class="sumo-card-heading"> <a href="/en-US/kb/how-reset-default-user-agent-firefox" data-event-name="link_click" data-event-parameters='{"link_name": "kb-article"}'> How to reset the default user agent on Firefox </a> </h2> <p>Learn how to reset your Firefox "user agent" so that websites can detect your correct browser and version and work the way they should.</p> <div id="document_metadata" class="has-border-top"> <span class="product tooltip-container"> Firefox <span class="tooltip">Firefox</span> </span> <span class="last-updated"> <img class="pencil" src="https://assets-prod.sumo.prod.webservices.mozgcp.net/static/pencil.e33c563f24c4f989.svg" /> <strong>Last updated:</strong> <span class="time"> <time datetime="2024-07-31T02:21:38.984248-07:00">7/31/24</time> </span> </span> </div> </div> </article> <article class="topic-article no-bottom-margin"> <div class="topic-article--icon-wrap"> <img class="topic-article--icon" src="https://assets-prod.sumo.prod.webservices.mozgcp.net/static/reader-mode.1d40422a5274c27c.svg" alt="" /> </div> <div class="topic-article--text"> <h2 class="sumo-card-heading"> <a href="/en-US/kb/Certificate-contains-the-same-serial-number-as-another-certificate" data-event-name="link_click" data-event-parameters='{"link_name": "kb-article"}'> Certificate contains the same serial number as another certificate </a> </h2> <p>Why Firefox may show you a Secure Connection Failed error when you try to access the configuration page for your router and what to do.</p> <div id="document_metadata" class="has-border-top"> <span class="product tooltip-container"> Firefox <span class="tooltip">Firefox</span> </span> <span class="last-updated"> <img class="pencil" src="https://assets-prod.sumo.prod.webservices.mozgcp.net/static/pencil.e33c563f24c4f989.svg" /> <strong>Last updated:</strong> <span class="time"> <time datetime="2019-03-10T03:07:29-07:00">3/10/19</time> </span> </span> </div> </div> </article> <article class="topic-article no-bottom-margin"> <div class="topic-article--icon-wrap"> <img class="topic-article--icon" src="https://assets-prod.sumo.prod.webservices.mozgcp.net/static/reader-mode.1d40422a5274c27c.svg" alt="" /> </div> <div class="topic-article--text"> <h2 class="sumo-card-heading"> <a href="/en-US/kb/where-go-developer-support" data-event-name="link_click" data-event-parameters='{"link_name": "kb-article"}'> Where to go for developer support </a> </h2> <p>Have questions about web development or Firefox Developer Edition? MDN Web Docs has many resources you'll need to build a better web. Learn more.</p> <div id="document_metadata" class="has-border-top"> <span class="product tooltip-container"> Firefox, Firefox for Android <span class="tooltip">Firefox, Firefox for Android</span> </span> <span class="last-updated"> <img class="pencil" src="https://assets-prod.sumo.prod.webservices.mozgcp.net/static/pencil.e33c563f24c4f989.svg" /> <strong>Last updated:</strong> <span class="time"> <time datetime="2024-11-19T03:42:46.425560-08:00">11/19/24</time> </span> </span> </div> </div> </article> <article class="topic-article no-bottom-margin"> <div class="topic-article--icon-wrap"> <img class="topic-article--icon" src="https://assets-prod.sumo.prod.webservices.mozgcp.net/static/reader-mode.1d40422a5274c27c.svg" alt="" /> </div> <div class="topic-article--text"> <h2 class="sumo-card-heading"> <a href="/en-US/kb/disable-firefox-sync" data-event-name="link_click" data-event-parameters='{"link_name": "kb-article"}'> Disable Firefox Sync </a> </h2> <p>Learn how to turn off Firefox Sync if you’d like to use your Mozilla account without syncing data such as, bookmarks, history and tabs.</p> <div id="document_metadata" class="has-border-top"> <span class="product tooltip-container"> Firefox, Mozilla Account <span class="tooltip">Firefox, Mozilla Account</span> </span> <span class="last-updated"> <img class="pencil" src="https://assets-prod.sumo.prod.webservices.mozgcp.net/static/pencil.e33c563f24c4f989.svg" /> <strong>Last updated:</strong> <span class="time"> <time datetime="2023-10-30T00:48:42-07:00">10/30/23</time> </span> </span> </div> </div> </article> <article class="topic-article no-bottom-margin"> <div class="topic-article--icon-wrap"> <img class="topic-article--icon" src="https://assets-prod.sumo.prod.webservices.mozgcp.net/static/reader-mode.1d40422a5274c27c.svg" alt="" /> </div> <div class="topic-article--text"> <h2 class="sumo-card-heading"> <a href="/en-US/kb/firefox-blocked-macos-15-sequoia-firewall-what-you" data-event-name="link_click" data-event-parameters='{"link_name": "kb-article"}'> Firefox blocked by macOS 15 Sequoia firewall - What you need to know </a> </h2> <p>Some macOS 15 users may have Firefox blocked by the firewall. Learn about the issue and how to help Mozilla investigate.</p> <div id="document_metadata" class="has-border-top"> <span class="product tooltip-container"> Firefox <span class="tooltip">Firefox</span> </span> <span class="last-updated"> <img class="pencil" src="https://assets-prod.sumo.prod.webservices.mozgcp.net/static/pencil.e33c563f24c4f989.svg" /> <strong>Last updated:</strong> <span class="time"> <time datetime="2024-09-24T16:44:01.219475-07:00">9/24/24</time> </span> </span> </div> </div> </article> <article class="topic-article no-bottom-margin"> <div class="topic-article--icon-wrap"> <img class="topic-article--icon" src="https://assets-prod.sumo.prod.webservices.mozgcp.net/static/reader-mode.1d40422a5274c27c.svg" alt="" /> </div> <div class="topic-article--text"> <h2 class="sumo-card-heading"> <a href="/en-US/kb/websites-look-wrong-or-appear-differently" data-event-name="link_click" data-event-parameters='{"link_name": "kb-article"}'> Websites look wrong or appear differently than they should </a> </h2> <p>This article explains how to fix problems with websites that display incorrectly in Firefox or don't work the way they should.</p> <div id="document_metadata" class="has-border-top"> <span class="product tooltip-container"> Firefox <span class="tooltip">Firefox</span> </span> <span class="last-updated"> <img class="pencil" src="https://assets-prod.sumo.prod.webservices.mozgcp.net/static/pencil.e33c563f24c4f989.svg" /> <strong>Last updated:</strong> <span class="time"> <time datetime="2024-07-31T02:47:07.712211-07:00">7/31/24</time> </span> </span> </div> </div> </article> <article class="topic-article no-bottom-margin"> <div class="topic-article--icon-wrap"> <img class="topic-article--icon" src="https://assets-prod.sumo.prod.webservices.mozgcp.net/static/reader-mode.1d40422a5274c27c.svg" alt="" /> </div> <div class="topic-article--text"> <h2 class="sumo-card-heading"> <a href="/en-US/kb/server-not-found-connection-problem" data-event-name="link_click" data-event-parameters='{"link_name": "kb-article"}'> Server Not Found - Troubleshoot connection problems </a> </h2> <p>If you can't connect to a website, you may see the Server Not Found error message. Learn how to troubleshoot and fix this error.</p> <div id="document_metadata" class="has-border-top"> <span class="product tooltip-container"> Firefox <span class="tooltip">Firefox</span> </span> <span class="last-updated"> <img class="pencil" src="https://assets-prod.sumo.prod.webservices.mozgcp.net/static/pencil.e33c563f24c4f989.svg" /> <strong>Last updated:</strong> <span class="time"> <time datetime="2022-10-22T06:17:46-07:00">10/22/22</time> </span> </span> </div> </div> </article> <article class="topic-article no-bottom-margin"> <div class="topic-article--icon-wrap"> <img class="topic-article--icon" src="https://assets-prod.sumo.prod.webservices.mozgcp.net/static/reader-mode.1d40422a5274c27c.svg" alt="" /> </div> <div class="topic-article--text"> <h2 class="sumo-card-heading"> <a href="/en-US/kb/task-manager-tabs-or-extensions-are-slowing-firefox" data-event-name="link_click" data-event-parameters='{"link_name": "kb-article"}'> Task Manager - see whether tabs or extensions are slowing down Firefox </a> </h2> <p>Firefox has a feature that lets you see how much memory and CPU resources are being used by tabs, extensions and other processes. Learn more.</p> <div id="document_metadata" class="has-border-top"> <span class="product tooltip-container"> Firefox <span class="tooltip">Firefox</span> </span> <span class="last-updated"> <img class="pencil" src="https://assets-prod.sumo.prod.webservices.mozgcp.net/static/pencil.e33c563f24c4f989.svg" /> <strong>Last updated:</strong> <span class="time"> 2 weeks, 4 days ago </span> </span> </div> </div> </article> <article class="topic-article no-bottom-margin"> <div class="topic-article--icon-wrap"> <img class="topic-article--icon" src="https://assets-prod.sumo.prod.webservices.mozgcp.net/static/reader-mode.1d40422a5274c27c.svg" alt="" /> </div> <div class="topic-article--text"> <h2 class="sumo-card-heading"> <a href="/en-US/kb/https-first" data-event-name="link_click" data-event-parameters='{"link_name": "kb-article"}'> HTTPS-First upgrades to secure connections </a> </h2> <p>From version 136, Firefox implements HTTPS-First and always attempts to connect securely. If a secure connection fails it falls back to an insecure connection.</p> <div id="document_metadata" class="has-border-top"> <span class="product tooltip-container"> Firefox <span class="tooltip">Firefox</span> </span> <span class="last-updated"> <img class="pencil" src="https://assets-prod.sumo.prod.webservices.mozgcp.net/static/pencil.e33c563f24c4f989.svg" /> <strong>Last updated:</strong> <span class="time"> 2 weeks, 3 days ago </span> </span> </div> </div> </article> <article class="topic-article no-bottom-margin"> <div class="topic-article--icon-wrap"> <img class="topic-article--icon" src="https://assets-prod.sumo.prod.webservices.mozgcp.net/static/reader-mode.1d40422a5274c27c.svg" alt="" /> </div> <div class="topic-article--text"> <h2 class="sumo-card-heading"> <a href="/en-US/kb/rate-your-firefox-experience-heartbeat" data-event-name="link_click" data-event-parameters='{"link_name": "kb-article"}'> Rate your Firefox experience, surveys and out of date messages (Heartbeat) </a> </h2> <p>You may be selected to rate Firefox or complete a survey. You may also see a notice to update Firefox. Learn more about these messages.</p> <div id="document_metadata" class="has-border-top"> <span class="product tooltip-container"> Firefox <span class="tooltip">Firefox</span> </span> <span class="last-updated"> <img class="pencil" src="https://assets-prod.sumo.prod.webservices.mozgcp.net/static/pencil.e33c563f24c4f989.svg" /> <strong>Last updated:</strong> <span class="time"> <time datetime="2022-06-06T10:39:33-07:00">6/6/22</time> </span> </span> </div> </div> </article> <article class="topic-article no-bottom-margin"> <div class="topic-article--icon-wrap"> <img class="topic-article--icon" src="https://assets-prod.sumo.prod.webservices.mozgcp.net/static/reader-mode.1d40422a5274c27c.svg" alt="" /> </div> <div class="topic-article--text"> <h2 class="sumo-card-heading"> <a href="/en-US/kb/solutions-can-not-create-temp-folder-archive-error" data-event-name="link_click" data-event-parameters='{"link_name": "kb-article"}'> Solutions for "Can not create temp folder archive" error when installing Firefox (Windows 10) </a> </h2> <p>Stuck with the "Can not create temp folder archive" error on 7-Zip when installing Firefox for Windows 10? This article will help you to solve the issue.</p> <div id="document_metadata" class="has-border-top"> <span class="product tooltip-container"> Firefox <span class="tooltip">Firefox</span> </span> <span class="last-updated"> <img class="pencil" src="https://assets-prod.sumo.prod.webservices.mozgcp.net/static/pencil.e33c563f24c4f989.svg" /> <strong>Created:</strong> <span class="time"> <time datetime="2021-06-06T16:17:51-07:00">6/6/21</time> </span> </span> </div> </div> </article> <article class="topic-article no-bottom-margin"> <div class="topic-article--icon-wrap"> <img class="topic-article--icon" src="https://assets-prod.sumo.prod.webservices.mozgcp.net/static/reader-mode.1d40422a5274c27c.svg" alt="" /> </div> <div class="topic-article--text"> <h2 class="sumo-card-heading"> <a href="/en-US/kb/windows-administrator-launcher-process-error-fix" data-event-name="link_click" data-event-parameters='{"link_name": "kb-article"}'> Drag and Drop errors with Firefox Launcher Process enabled and Windows UAC disabled - How to Fix </a> </h2> <p>How to fix Firefox drag-and-drop errors when running Windows as Administrator with UAC disabled and the Launcher Process enabled.</p> <div id="document_metadata" class="has-border-top"> <span class="product tooltip-container"> Firefox, Firefox for Enterprise <span class="tooltip">Firefox, Firefox for Enterprise</span> </span> <span class="last-updated"> <img class="pencil" src="https://assets-prod.sumo.prod.webservices.mozgcp.net/static/pencil.e33c563f24c4f989.svg" /> <strong>Last updated:</strong> <span class="time"> <time datetime="2020-07-18T12:37:53-07:00">7/18/20</time> </span> </span> </div> </div> </article> <article class="topic-article no-bottom-margin"> <div class="topic-article--icon-wrap"> <img class="topic-article--icon" src="https://assets-prod.sumo.prod.webservices.mozgcp.net/static/reader-mode.1d40422a5274c27c.svg" alt="" /> </div> <div class="topic-article--text"> <h2 class="sumo-card-heading"> <a href="/en-US/kb/identify-problems-third-party-modules-firefox-windows" data-event-name="link_click" data-event-parameters='{"link_name": "kb-article"}'> Identify problems caused by third-party modules in Firefox for Windows </a> </h2> <p>Identify problems caused by third-party modules in Firefox for Windows.</p> <div id="document_metadata" class="has-border-top"> <span class="product tooltip-container"> Firefox <span class="tooltip">Firefox</span> </span> <span class="last-updated"> <img class="pencil" src="https://assets-prod.sumo.prod.webservices.mozgcp.net/static/pencil.e33c563f24c4f989.svg" /> <strong>Last updated:</strong> <span class="time"> <time datetime="2023-03-10T05:33:11-08:00">3/10/23</time> </span> </span> </div> </div> </article> <article class="topic-article no-bottom-margin"> <div class="topic-article--icon-wrap"> <img class="topic-article--icon" src="https://assets-prod.sumo.prod.webservices.mozgcp.net/static/reader-mode.1d40422a5274c27c.svg" alt="" /> </div> <div class="topic-article--text"> <h2 class="sumo-card-heading"> <a href="/en-US/kb/x-mouse-button-control-firefox-110" data-event-name="link_click" data-event-parameters='{"link_name": "kb-article"}'> X-Mouse Button Control in Firefox 110 </a> </h2> <p>Learn about an issue with X-Mouse Button Control in Firefox 110 for Windows.</p> <div id="document_metadata" class="has-border-top"> <span class="product tooltip-container"> Firefox <span class="tooltip">Firefox</span> </span> <span class="last-updated"> <img class="pencil" src="https://assets-prod.sumo.prod.webservices.mozgcp.net/static/pencil.e33c563f24c4f989.svg" /> <strong>Last updated:</strong> <span class="time"> <time datetime="2023-03-02T20:45:12-08:00">3/2/23</time> </span> </span> </div> </div> </article> <article class="topic-article no-bottom-margin"> <div class="topic-article--icon-wrap"> <img class="topic-article--icon" src="https://assets-prod.sumo.prod.webservices.mozgcp.net/static/reader-mode.1d40422a5274c27c.svg" alt="" /> </div> <div class="topic-article--text"> <h2 class="sumo-card-heading"> <a href="/en-US/kb/how-resolve-weak-crypto-error-messages-firefox" data-event-name="link_click" data-event-parameters='{"link_name": "kb-article"}'> How to resolve weak crypto error messages on Firefox </a> </h2> <p>When connecting to a website that uses an invalid TLS certificate or weak encryption, Firefox will display an error page saying "Your connection is not secure".</p> <div id="document_metadata" class="has-border-top"> <span class="product tooltip-container"> Firefox <span class="tooltip">Firefox</span> </span> <span class="last-updated"> <img class="pencil" src="https://assets-prod.sumo.prod.webservices.mozgcp.net/static/pencil.e33c563f24c4f989.svg" /> <strong>Created:</strong> <span class="time"> <time datetime="2015-11-09T05:22:10-08:00">11/9/15</time> </span> </span> </div> </div> </article> <article class="topic-article no-bottom-margin"> <div class="topic-article--icon-wrap"> <img class="topic-article--icon" src="https://assets-prod.sumo.prod.webservices.mozgcp.net/static/reader-mode.1d40422a5274c27c.svg" alt="" /> </div> <div class="topic-article--text"> <h2 class="sumo-card-heading"> <a href="/en-US/kb/64-bit-firefox-crashes-citrixs-xenapp-vm" data-event-name="link_click" data-event-parameters='{"link_name": "kb-article"}'> 64-bit Firefox crashes with Citrix's XenApp VM </a> </h2> <p>The API hooks from Citrix XenApp 7.13 VDA do not work with 64-bit Firefox. How to find a workaround.</p> <div id="document_metadata" class="has-border-top"> <span class="product tooltip-container"> Firefox <span class="tooltip">Firefox</span> </span> <span class="last-updated"> <img class="pencil" src="https://assets-prod.sumo.prod.webservices.mozgcp.net/static/pencil.e33c563f24c4f989.svg" /> <strong>Last updated:</strong> <span class="time"> <time datetime="2017-06-30T02:55:08-07:00">6/30/17</time> </span> </span> </div> </div> </article> <article class="topic-article no-bottom-margin"> <div class="topic-article--icon-wrap"> <img class="topic-article--icon" src="https://assets-prod.sumo.prod.webservices.mozgcp.net/static/reader-mode.1d40422a5274c27c.svg" alt="" /> </div> <div class="topic-article--text"> <h2 class="sumo-card-heading"> <a href="/en-US/kb/how-fix-error-when-trying-open-telegram-or-slack" data-event-name="link_click" data-event-parameters='{"link_name": "kb-article"}'> How to fix an error when trying to open Telegram or Slack on Firefox </a> </h2> <p>How to fix the NS_ERROR_DOM_ABORT_ERR while trying to open web.telegram.org or app.slack.com on Firefox 87 or above.</p> <div id="document_metadata" class="has-border-top"> <span class="product tooltip-container"> Firefox <span class="tooltip">Firefox</span> </span> <span class="last-updated"> <img class="pencil" src="https://assets-prod.sumo.prod.webservices.mozgcp.net/static/pencil.e33c563f24c4f989.svg" /> <strong>Last updated:</strong> <span class="time"> <time datetime="2022-08-21T22:50:20-07:00">8/21/22</time> </span> </span> </div> </div> </article> <article class="topic-article no-bottom-margin"> <div class="topic-article--icon-wrap"> <img class="topic-article--icon" src="https://assets-prod.sumo.prod.webservices.mozgcp.net/static/reader-mode.1d40422a5274c27c.svg" alt="" /> </div> <div class="topic-article--text"> <h2 class="sumo-card-heading"> <a href="/en-US/kb/difficulties-opening-or-using-website-firefox-100" data-event-name="link_click" data-event-parameters='{"link_name": "kb-article"}'> Difficulties opening or using a website in Firefox 100 </a> </h2> <p>A potential temporary solution if a web page is not opening correctly in Firefox 100.</p> <div id="document_metadata" class="has-border-top"> <span class="product tooltip-container"> Firefox <span class="tooltip">Firefox</span> </span> <span class="last-updated"> <img class="pencil" src="https://assets-prod.sumo.prod.webservices.mozgcp.net/static/pencil.e33c563f24c4f989.svg" /> <strong>Last updated:</strong> <span class="time"> <time datetime="2022-06-06T09:36:23-07:00">6/6/22</time> </span> </span> </div> </div> </article> <article class="topic-article no-bottom-margin"> <div class="topic-article--icon-wrap"> <img class="topic-article--icon" src="https://assets-prod.sumo.prod.webservices.mozgcp.net/static/reader-mode.1d40422a5274c27c.svg" alt="" /> </div> <div class="topic-article--text"> <h2 class="sumo-card-heading"> <a href="/en-US/kb/firefox-hangs-when-copying-suggested-actions-windows-11" data-event-name="link_click" data-event-parameters='{"link_name": "kb-article"}'> Firefox hangs when copying with Suggested Actions enabled on Windows 11 - What to do </a> </h2> <p>Firefox can freeze or stop responding when copying, with the Suggested Actions feature enabled on Windows 11. 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data-event-parameters='{"link_name": "kb-article"}'> Firefox is stuck in Troubleshoot Mode </a> </h2> <p>Learn why Firefox may start in Troubleshoot Mode (previously known as "Safe Mode") when you expect it to start normally and how to fix it.</p> <div id="document_metadata" class="has-border-top"> <span class="product tooltip-container"> Firefox <span class="tooltip">Firefox</span> </span> <span class="last-updated"> <img class="pencil" src="https://assets-prod.sumo.prod.webservices.mozgcp.net/static/pencil.e33c563f24c4f989.svg" /> <strong>Last updated:</strong> <span class="time"> <time datetime="2023-03-11T23:28:44-08:00">3/11/23</time> </span> </span> </div> </div> </article> <article class="topic-article no-bottom-margin"> <div class="topic-article--icon-wrap"> <img class="topic-article--icon" src="https://assets-prod.sumo.prod.webservices.mozgcp.net/static/reader-mode.1d40422a5274c27c.svg" alt="" /> </div> <div class="topic-article--text"> <h2 class="sumo-card-heading"> <a href="/en-US/kb/firefox-repeatedly-opens-empty-tabs-or-windows" data-event-name="link_click" data-event-parameters='{"link_name": "kb-article"}'> Firefox repeatedly opens empty tabs or windows after you click on a link </a> </h2> <p>Firefox may repeatedly open empty tabs or windows after you click on a link, forcing you to close Firefox. Learn how to fix this problem.</p> <div id="document_metadata" class="has-border-top"> <span class="product tooltip-container"> Firefox <span class="tooltip">Firefox</span> </span> <span class="last-updated"> <img class="pencil" src="https://assets-prod.sumo.prod.webservices.mozgcp.net/static/pencil.e33c563f24c4f989.svg" /> <strong>Last updated:</strong> <span class="time"> <time datetime="2024-09-02T11:37:31.756016-07:00">9/2/24</time> </span> </span> </div> </div> </article> <article class="topic-article no-bottom-margin"> <div class="topic-article--icon-wrap"> <img class="topic-article--icon" src="https://assets-prod.sumo.prod.webservices.mozgcp.net/static/reader-mode.1d40422a5274c27c.svg" alt="" /> </div> <div class="topic-article--text"> <h2 class="sumo-card-heading"> <a href="/en-US/kb/fix-video-audio-problems-firefox-windows" data-event-name="link_click" data-event-parameters='{"link_name": "kb-article"}'> Fix video and audio problems on Firefox for Windows N editions </a> </h2> <p>If Firefox has trouble playing video or music on a Windows computer, you can install the Media Feature Pack, if it's missing. 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to start it and other solutions don't work, a clean reinstall can often fix the problem.</p> <div id="document_metadata" class="has-border-top"> <span class="product tooltip-container"> Firefox <span class="tooltip">Firefox</span> </span> <span class="last-updated"> <img class="pencil" src="https://assets-prod.sumo.prod.webservices.mozgcp.net/static/pencil.e33c563f24c4f989.svg" /> <strong>Last updated:</strong> <span class="time"> <time datetime="2022-11-09T03:23:03-08:00">11/9/22</time> </span> </span> </div> </div> </article> <article class="topic-article no-bottom-margin"> <div class="topic-article--icon-wrap"> <img class="topic-article--icon" src="https://assets-prod.sumo.prod.webservices.mozgcp.net/static/reader-mode.1d40422a5274c27c.svg" alt="" /> </div> <div class="topic-article--text"> <h2 class="sumo-card-heading"> <a href="/en-US/kb/problems-with-email-how-to-find-help" data-event-name="link_click" data-event-parameters='{"link_name": "kb-article"}'> Problems with email and 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