Mozilla Firefox
25 questions
How to clear cache in Firefox?
•Press Ctrl+Shift+Delete.
•In the 'Clear History' window, select 'Everything'.
•Check 'Cache'.
•Click 'Clear Now'.
•Alternative: Menu → Settings → Privacy & Security → Cookies and Site Data → Clear Data.
How to enable tracking protection in Firefox?
•Menu → Settings → Privacy & Security.
•In the 'Enhanced Tracking Protection' section.
•Choose level: Standard, Strict, Custom.
•Strict blocks more but may break site functionality.
How to restore a Firefox session?
•Firefox offers to restore the session after a crash automatically.
•If not: enter about:sessionrestore in the address bar.
•Manual restore: the profile folder contains sessionstore-backups.
•Menu → History → Restore Previous Session.
How to disable auto-play of videos in Firefox?
•Menu → Settings → Privacy & Security.
•'Permissions' section → Autoplay → Settings.
•In the dropdown, select 'Block Audio and Video'.
•Add exceptions for specific sites.
How to sync Firefox between devices?
•Menu → Sign in to Firefox.
•Create an account or sign in.
•Choose what to sync.
•On another device, sign in with the same account.
•Sync settings: Settings → Sync.
How to import bookmarks into Firefox?
•Menu → Bookmarks → Manage Bookmarks.
•Or press Ctrl+Shift+O.
•Import and Backup → Import Bookmarks from HTML.
•Or 'Import Data from Another Browser' for full import.
How to enable private mode in Firefox?
•Press Ctrl+Shift+P (Windows/Linux) or Cmd+Shift+P (Mac).
•Or menu → New Private Window.
•In private mode, history is not saved.
•Firefox also blocks trackers in private mode.
How to change the homepage in Firefox?
•Menu → Settings → Home.
•In the 'Homepage and new windows' section.
•Choose: Firefox Home, Custom URLs, or Blank Page.
•Enter the address for your custom page.
How to update Firefox?
•Menu → Help → About Firefox.
•Firefox will check for updates automatically.
•Click 'Restart to update'.
•Firefox updates automatically by default.
How to manage Firefox extensions?
•Menu → Add-ons and themes.
•Or type about:addons in the address bar.
•The 'Extensions' section shows installed extensions.
•You can disable, remove, or configure each one.
How to create a profile in Firefox?
•Type about:profiles in the address bar.
•Click 'Create a New Profile'.
•Follow the creation wizard.
•Profiles are isolated from each other.
•Launch with a profile: firefox -P profile_name.
How to view saved passwords in Firefox?
•Menu → Passwords.
•Or Settings → Privacy & Security → Logins and Passwords → Saved Logins.
•Click the eye icon to show passwords.
•It is recommended to set a master password.
How to enable DNS over HTTPS in Firefox?
•Menu → Settings → Privacy & Security.
•Scroll to 'DNS over HTTPS'.
•Choose the protection level.
•Select a provider: Cloudflare, NextDNS, or custom.
•Enhances privacy of DNS queries.
How to block a website in Firefox?
•Install the BlockSite or LeechBlock extension.
•Add sites to the blacklist.
•Configure blocking schedule.
•Use built-in OS tools for parental control.
How to export bookmarks from Firefox?
•Menu → Bookmarks → Manage Bookmarks.
•Import and Backup → Export Bookmarks to HTML.
•Choose the save location.
•For a full backup: Backup → JSON file.
How to open developer tools in Firefox?
•Press F12 or Ctrl+Shift+I.
•Or menu → Web Developer → Developer Tools.
•Tabs: Inspector, Console, Debugger, Network, Styles.
•Ctrl+Shift+C to select an element.
How to enable containers in Firefox?
•Install the Firefox Multi-Account Containers extension.
•Or enable built-in containers: about:config → privacy.userContext.enabled = true.
•Containers isolate cookies between sites.
•Useful for managing multiple accounts.
How to reset Firefox to factory settings?
•Menu → Help → Troubleshooting Information.
•Click 'Refresh Firefox'.
•Or enter about:support and press the button.
•Bookmarks and passwords are saved, extensions and settings will be removed.
How to change the page zoom in Firefox?
•Ctrl++ to zoom in, Ctrl+- to zoom out.
•Ctrl+0 to reset to 100%.
•For permanent zoom: Settings → General → Zoom.
•You can set zoom only for text.
How to disable notifications in Firefox?
•Menu → Settings → Privacy & Security.
•'Permissions' section → Notifications → Settings.
•Check 'Block new requests'.
•Remove permissions for individual sites.
Mozilla Firefox: how to speed up startup and reduce memory usage?
Start with simple steps: update the browser, clear cache/cookies for problematic sites, and disable extensions one by one.
Mozilla Firefox: how to configure privacy and tracker protection?
Test in private mode and in another browser. This quickly shows whether the problem is with the site or with your profile/extensions.
Mozilla Firefox: how to manage profiles and transfer data?
Enable synchronization but keep 2FA and backup codes. Security is more important than convenience.
Mozilla Firefox: how to diagnose extension issues?
It is useful to configure a password manager and tracker blocker, but do not install dozens of extensions at once.
Mozilla Firefox: why doesn't a website open or why do you see a certificate error?
If the question is about «Mozilla Firefox», check DNS/proxy/VPN and certificates. Many errors are network-related, not website issues.