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Windows 10 reached EOS (end of support) on October 14, 2025. For more information, see this article.

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Performance and connectivity

Performance and connectivity

Deal with error messages, crashing applications, connectivity issues, and slow performance.

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Secure connection and security warning error pages in Firefox

Troubleshoot time-related errors on secure websites

Fix "The bookmarks and history system will not be functional" error message

Fix error “Website will not allow Firefox to display the page.”

Captive portal detection

Connection settings in Firefox

Troubleshoot security error codes on secure websites

Use Troubleshoot Mode in Firefox

Troubleshoot and diagnose Firefox problems

How do I report a broken site in Firefox desktop?

Fix Firefox using too much memory or CPU resources

Resist Fingerprinting

What do the security warning codes mean?

Task Manager - see whether tabs or extensions are slowing down Firefox

Firefox DNS over HTTPS

Warning Unresponsive script - What it means and how to fix it

Certificate contains the same serial number as another certificate

Use the Troubleshooting Information page to help fix Firefox issues

Where to go for developer support

Firefox hangs or is not responding - How to fix

Firefox can't load websites but other browsers can

Quick fixes if your Firefox slows down

DNS over HTTPS (DoH) FAQs

Unload inactive tabs to save system memory in Firefox

Server Not Found - Troubleshoot connection problems

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

Firefox takes a long time to start up

Firefox says it's just updated every time it starts - how to fix

"Firefox is already running but is not responding" error - How to fix

Disable Firefox Sync

How to let Firefox use the internet on your Windows computer

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

HTTPS-First upgrades to secure connections

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Websites say that Firefox is outdated or incompatible even though it's the latest version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 does not work - Common fixes to get you back up and running

Memory constraints, Firefox performance and Firewalls

Rate your Firefox experience, surveys and out of date messages (Heartbeat)

How to resolve weak crypto error messages on Firefox

64-bit Firefox crashes with Citrix's XenApp VM

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

Unsent crash reports in Firefox

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

Problems with email and how to find help

Fix video and audio problems on Firefox for Windows N editions

Avoid crashes - Tips and tricks

Firefox keeps crashing at startup

Home page with pipe character opens extra tabs when Firefox starts

How to run Firefox when your profile is missing or inaccessible

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