Download Firefox Systems and Languages What's New Privacy Performance and connectivity Deal with error messages, crashing applications, connectivity issues, and slow performance. Dena All articles and threads Crashing and slow performance Site breakages In English How to troubleshoot time related errors on secure websites Captive portal detection How to troubleshoot security error codes on secure websites Connection settings in Firefox What do the security warning codes mean? Manage the devices linked to your Mozilla account Firefox blocked by macOS 15 Sequoia firewall - What you need to know How to let Firefox use the internet on your Windows computer Disable Firefox Sync Firefox can't load websites but other browsers can Browsing history in Firefox - View the websites you have visited Using a Primary Password with Sync Server Not Found - Troubleshoot connection problems How to resolve weak crypto error messages on Firefox Resist Fingerprinting Address screen sharing issues with Firefox on macOS 15 Sequoia