Add 'Quit' action button in Tor Browser for Android persistent notification.
If you press the back button in Tor Browser for Android, while you exit out of the application you don't actually quit it. So then you need to go back, click on the kebab menu, scroll all the way down to quit and then you finally quit Tor Browser.
An enhancement would be to add the 'Quit' action button in the persistent notification next to the 'New Identity' button so you can quit directly from the notification area. Something similar exists for the Incognito mode in Chrome where you tap on the notification to close all Incognito tabs.