ryb0rg, I second Riddick's suggestion of Sandboxie.
Understanding the main effect of how the program works can help it make it uncomplicated.
With the use of Sandboxie's "sandbox", for your browsers, all changes made (added extensions, updates to both extensions & browsers, & downloads not recovered) disappear as though they'd never occured while protecting your system from unwanted changes.
A more secure method than the built in password managers provided by either FireFox or Chrome for organizing passwords is called LastPass. It securely accesses all passwords with the use of a single master password. It's free, utilizes encryption security, and makes this part of my computing life far less involved with suffering the headaches I no longer have!
Thank you for sharing, and allowing us to enhace you configuration (by your leave!).