As the title says, suddenly Firefox starts on startup. It randomly opens the last session or just a blank window. Once or twice with the added tab of the microsoft help page. What could cause this? A Win10 or Firefox update?
That's a pretty easy fix, Firefox would start up in the background and hog a bunch of my resources before I fixed it myself.
Here's what you have to do:
1. Open Firefox and enter about:config into the URL Address bar and say yes when it warns you that messing with the settings of firfox could possibly damage your PC (it won't).
2. Use the search bar in about:config and search for toolkit.winRegisterApplicationRestart
3. Change the value of the setting from true to false
And that should fix your problem
Personally, I think it's probably the result of the new feature of 1903 that allows the system to start again where you left off being wonky.
I have discussed this over the last couple of days here on TH. I have had periods where Firefox was always starting when I started the system, which eventually went away on its own, and after which I had another web browser.
See the topic:
windows 10 now boots and launches internet explorer