Waterfox

I've migrated both of my profiles on my Linux Mint desktop to Waterfox. I installed from tar which allows me to more easily integrate with Keepass -- Details in this thread. If you're using Keepass Browser integration, you'll need to install this way. But if you use a different password manager, you should be fine with flatpak or whatever your system uses for package management.

Migration from Firefox did not work -- I suspect this is a limitation on Waterfox as I also tried migration within Windows. I did attempt a straight profile copy, which did not work. While history, cookies, etc. looked like they came over fine, extensions struggled and it was hard to tell whether they actually were migrated.

So unfortunately, it's not an easy transition and it will be highly manual. Backup your bookmarks, passwords, etc. and import them. This also means any customization you made on addons (e.g. ublock origin settings, etc) will need to be imported as well. It helps if you have both Firefox and Waterfox open side by side and you can just go from one to the other.

My Windows laptop will be next week. I want to give my main driver to "bake" a bit before I do this on Windows.

So...AMA