Recently my browser of choice, Mozilla Firefox, started being weird and kept asking if I’d restore the previous session or start a new session whenever I started it. This is weird simply because I’m a bit of a fanatic geek when it comes to shutting down machines and applications properly, i.e. I always make sure the apps I’m using are shutdown properly when I’ve finished with them.

A complete removal and reinstall of Firefox fixes the problem, I know that much - I rebuilt my machine recently and the problem didn’t happen until I configured Firefox with my own preferences. This means it had to be something I had changed. I went through all the stuff I changed and found the culprit. When I configure Firefox I always set the “When Firefox starts” option to “Show my windows and tabs from last time”. This option, combined with an empty setting for the “Home Page” settings appears to cause Firefox to prompt for the session mode every time it’s started.

I could leave the “Show my windows and tabs from last time” option selected but I had to enter about:blank into the “Home Page” box before the problem stopped. Here’s a screenshot of the settings tab I’m talking about (your “Save files to” setting will probably be different so you can ignore that).

Firefox Settings Screenshot

Weird problem but that’s how I fixed it. Hope it helps someone!