Sorry if I explained myself incorrectly. My main point isn't concurrent usage of profiles. I lack the necesary knowledge on how to correctly install two differ

Sorry if I explained myself incorrectly. My main point isn't concurrent usage of profiles. I lack the necesary knowledge on how to correctly install two different FF versions and have them accesible with their respective icons. In my case, FF dev version and the one discussed in the article to help out with bug testing/development. The issue is since I'm on Debian, auto update does not work. From my limited understanding, I would need to install FF 57 in its own directory. For this one I don't need a profile. But I don't know how to install it and have it accesible either by command line or the FF icon that comes with the browser since I already have my main FF I want to keep. The second part is regarding the profile, sync with the other browser I recently installed.... I was about to go down a mental rabbit hole :) The problem is, the lack of noob friendly documentation. I know I could figure it out if I research the issue through different topics on Linux administration. I was hoping that maybe someone knew of a tutorial which talked about the different steps on how to install Firefox on a nix system, explaining the different concepts as if I were a five year old. The best I've managed to find is a tutorial laying out the steps. But it didn't explain the concepts behind those steps. That tutorial mentioned how to replace debians FF from the repo. But whenever a new version comes out I would need to delete it and unpack the new one, linking it to the old icon. I hope it's clear now. Thanks for the reply.