Here is how you can reduce the number of closed tabs that Firefox tracks:

(1) In a new tab, type or paste about:config in the address bar and press Enter/Return. Click the button promising to be careful or accepting the risk.

(2) In the search box above the list, type or paste sess and pause while the list is filtered

(3) Double-click the browser.sessionstore.max_tabs_undo preference to display a dialog where you can enter the desired value, which in your case might be 0 and then click OK

(4) If you wish, double-click the browser.sessionstore.max_windows_undo preference to display a dialog where you can enter the desired value, which in your case might be 0 and then click OK

Actually, wait, that is the regular mode setting. I am not aware of a separate setting for private windows. You'll need to close the window to flush that. Or maybe there's an add-on that can do it.

Please add a link on history sidebar to remove recently removed tabs.

Please add a link on history sidebar to remove recently removed tabs.

Please add a link on history sidebar to remove recently removed tabs in Private or Regular mode.

Hi pdeavilla99, to propose changes to future versions of Firefox, you may want to submit suggestions through one or more of the following links:

• Feedback: https://qsurvey.mozilla.com/s3/FirefoxInput/
• Discourse: https://discourse.mozilla.org/c/firefox-development
• Reddit: https://www.reddit.com/r/firefox/
• Twitter: https://twitter.com/firefox
• Facebook: https://www.facebook.com/Firefox