Firefox for Android users might notice their login sessions vanishing after a regular update. This isn’t just annoying—it’s confusing when the browser suddenly demands you sign in again to your Google or other accounts.

It’s not your fault, and it’s not a security issue. The fix is simple if you know where to look.

Firefox browser with disconnected icon

1. Check Sync Settings

Your Firefox sync might be accidentally disabled or misconfigured after an update. This breaks automatic sign-in across devices and resets session data.

To verify:

  • Open Firefox → tap the three dots menu
  • Select "Settings" → "Sync"
  • Ensure your account is selected under "Account"
  • If it’s not, sign in again and re-enable sync
Firefox sync settings with active account

2. Clear Cache (Not Data)

Cached data can sometimes interfere with login states after updates. Clearing the cache resets temporary files without deleting your bookmarks or history.

To clear cache:

  • Go to Firefox → Settings → Privacy & Security
  • Select "Clear Browsing Data"
  • Choose "Cached Images and Files" only, then tap "Clear"
Firefox cache settings screen

3. Update Firefox from the Play Store

If you’ve installed an unofficial or outdated version of Firefox, it can cause login issues. Always get the latest update directly through the Google Play Store.

Before updating:

  • Back up your bookmarks via "Sync"
  • Check for updates in the Play Store app

Final thoughts

This issue usually happens because of a sync misconfiguration or an incomplete update. Once fixed, Firefox will stay logged in after future updates.

You won’t need to reset anything or lose your data—just follow these steps and you’re back to normal.