Since a few months, firefox by default doesn't switch from incognito back to normal mode when I close the only remaining incognito tab. Can probably be attributed to increased privacy, I suppose, encouraging the use of incognito mode. But there's no setting to change that back. Over time, more of these minor annoyances appear which I'd need to dig in my memory for. Luckily, it's a relatively small price to pay, overall I'm just happy to have adblocking in the browser.