Browser privacy settings are useful when they match what you want to limit: tracking across sites, saved browsing data, site permissions, or automatic sign-in. Start by naming the concern rather than switching every control to its strictest level. Then test the pages you depend on.
Mistake: treating a private window as invisibility
A private window mainly changes what the browser keeps locally after the session. It does not make an account login or a website interaction anonymous. The FTC's privacy overview explains that websites and apps can collect information about use and devices. If your concern is a shared computer, also review browser profiles, saved passwords, and whether you signed out of accounts.
Mistake: enabling strict blocking without checking effects
Mozilla's Enhanced Tracking Protection guide describes Standard and Strict modes and notes that stronger blocking can make parts of a site fail. If a legitimate form or payment page stops working, test a site-specific exception before weakening protection everywhere. Record the exception so it can be removed later.
Check permissions and stored data
Review which sites have access to location, camera, microphone, and notifications. Remove permissions that no longer serve a purpose. Clear data for a specific site when troubleshooting rather than erasing every session without understanding the cost. Browser menus vary, so use the vendor's current help page for exact paths.
Better next step
Choose a baseline protection level, update the browser, and test a few important sites. Keep security separate from privacy: a tracker blocker does not fix a stolen password, and clearing cookies does not remove data a company already received. Revisit settings after major browser updates or when a site behaves unexpectedly.
Sources
- Enhanced Tracking Protection in Firefox for desktop — Mozilla Support
- How Websites and Apps Collect and Use Your Information — Federal Trade Commission