I guess you can fake an SSB in firefox by some hacking. I don't know how much work you want to put into this but here a sketch of an idea.
-
Create a new Profile in firefox: open
about:profilesclick in create new profile and give it the name of the SSB application you want to create. -
Open firefox in the new profile by running the command
firefox --no-remote -P "ProfileName" -
Check if you are in the correct profile by opening
about:support, in the information table look for Profile Directory. The path must end in "ProfileName". Click in Open Directory.