If you accumulate numerous open tabs over time and do not want to have to manually close them, you can enable Firefox for Android to automatically close tabs after one day, one week or one month. Firefox won’t auto-close tabs by default.

Change your auto-close tab settings

1. Tap the three-dot menu button.
   
2. Tap Settings.
3. Tap Tabs.
4. Under Close tabs, select a time period:
   • Never (default setting)
   • After one day
   • After one week
   • After one month

Open tabs not visited longer than the selected period will be closed automatically.