Performance and connectivity Deal with error messages, crashing applications, connectivity issues, and slow performance. In Engels Secure connection and security warning error pages in Firefox Troubleshoot time-related errors on secure websites Fix error “Website will not allow Firefox to display the page.” Fix "The bookmarks and history system will not be functional" error message Connection settings in Firefox Troubleshoot security error codes on secure websites Captive portal detection Unload inactive tabs to save system memory in Firefox Resist Fingerprinting Use Troubleshoot Mode in Firefox Firefox DNS over HTTPS Task Manager - see whether tabs or extensions are slowing down Firefox Firefox can't load websites but other browsers can Warning Unresponsive script - What it means and how to fix it Firefox uses too much memory or CPU resources - How to fix What do the security warning codes mean? How do I report a broken site in Firefox desktop? Troubleshoot and diagnose Firefox problems Use the Troubleshooting Information page to help fix Firefox issues Certificate contains the same serial number as another certificate Quick fixes if your Firefox slows down Disable Firefox Sync Where to go for developer support DNS over HTTPS (DoH) FAQs Firefox hangs or is not responding - How to fix How to let Firefox use the internet on your Windows computer HTTPS-First upgrades to secure connections How to reset the default user agent on Firefox Websites look wrong or appear differently than they should How to fix the Update Failed error message when updating Firefox Server Not Found - Troubleshoot connection problems Firefox takes a long time to start up Rate your Firefox experience, surveys and out of date messages (Heartbeat) 64-bit Firefox crashes with Citrix's XenApp VM Drag and Drop errors with Firefox Launcher Process enabled and Windows UAC disabled - How to Fix Firefox blocked by macOS 15 Sequoia firewall - What you need to know Firefox uses too many CPU resources - How to fix Websites say that Firefox is outdated or incompatible even though it's the latest version Firefox says it's just updated every time it starts - how to fix Firefox does not work - Common fixes to get you back up and running "Firefox is already running but is not responding" error - How to fix Memory constraints, Firefox performance and Firewalls How to resolve weak crypto error messages on Firefox How to fix an error when trying to open Telegram or Slack on Firefox Solutions for "Can not create temp folder archive" error when installing Firefox (Windows 10) Identify problems caused by third-party modules in Firefox for Windows Difficulties opening or using a website in Firefox 100 Firefox hangs when copying with Suggested Actions enabled on Windows 11 - What to do X-Mouse Button Control in Firefox 110 Address screen sharing issues with Firefox on macOS 15 Sequoia Troubleshoot Firefox crashes (closing or quitting unexpectedly) Firefox is stuck in Troubleshoot Mode Firefox repeatedly opens empty tabs or windows after you click on a link Avoid crashes - Tips and tricks Firefox keeps crashing at startup Problems with email and how to find help Fix video and audio problems on Firefox for Windows N editions Home page with pipe character opens extra tabs when Firefox starts How to run Firefox when your profile is missing or inaccessible