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Software Conspiracy

Browser Errors

Firefox not responding — How to fix on Windows

Firefox 'not responding' on Windows traces to: a corrupted profile, an add-on stuck in an infinite loop, or hardware acceleration fighting with a GPU driver.

Time
15 min
Difficulty
easy
Applies to
Windows 11, Windows 10
Updated
May 25, 2026

Symptoms

  • Firefox freezes for 5-30 seconds at random
  • Tabs go white and don't load
  • CPU usage spikes from a Firefox process

Likely causes

  • Corrupted places.sqlite (history database)
  • Add-on with a memory leak
  • Hardware acceleration on an unstable GPU driver
  • Antivirus scanning Firefox cache

How to fix it — step by step

  1. 01

    Refresh Firefox

    about:support → click Refresh Firefox. Keeps bookmarks, passwords, history; removes add-ons and theme tweaks.

  2. 02

    Disable hardware acceleration

    Settings → General → Performance → uncheck Use recommended performance settings → uncheck Use hardware acceleration when available. Restart.

  3. 03

    Start in Troubleshoot Mode

    Help menu → Troubleshoot Mode. Disables all add-ons. If freezing stops, an add-on is the cause.

  4. 04

    Add Firefox folder to antivirus exclusions

    Add %APPDATA%\Mozilla\ and %LOCALAPPDATA%\Mozilla\ as exclusions in Defender / your AV.

Frequently Asked Questions

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