Firefox Android Bug Breaks Keyboard Incognito Mode in Private Tabs

A recent bug in Firefox for Android meant that some users browsing in Private tabs weren’t as private as they thought. When searching in Private tabs, the keyboard did not switch to incognito mode and could record user input.

Who Was Affected?

The issue was tied to Firefox’s new “compose toolbar” for Private browsing, which Mozilla has been testing with a staged rollout. If you manually enabled the toolbar or were enrolled in the experiment, you may have been affected.

Users with the “default toolbar” were not impacted. Mozilla tests confirmed the problem across popular keyboards, including SwiftKey and Gboard, while Samsung Keyboard showed mixed results.

Firefox for Android Bug Broke Keyboard in Incognito Mode in Private Tabs, Issue Fixed in Beta

We also confirmed the issue is present in Firefox Android 143.0.2 when the compose toolbar is enabled in Private tabs, where the keyboard does not switch to incognito mode. Check the screenshots for reference.

Private browsing is designed to ensure your history, searches, and credentials don’t leave traces. If the keyboard isn’t in incognito mode, typed input may be stored in its history and could resurface later through autosuggestions or sync, exposing sensitive information.

That’s why it’s necessary to check that the keyboard is in incognito mode when searching in Private tabs, and not in this mode when searching in normal tabs.

Fix in Progress:

Mozilla has already patched the issue in Firefox 144 beta 6, confirming that SwiftKey and Gboard now properly switch to incognito mode in Private tabs. Firefox 144 is scheduled for release on October 14, but today’s Firefox 144.0.3 release notes did not mention this fix. It’s not clear yet if the fix will come out before the full update.

“Most users weren’t affected, but for those with the new toolbar, this was still a major privacy concern.

For now, users who rely on Private browsing should double-check their keyboard behavior in Firefox for Android until the fix is widely available.

That’s not all. Mozilla is redesigning the Firefox menu on Android and now supports native translations.