Epichrome is a fantastic solution for site-specific browsers (AKA SSBs). Yet, I prefer Firefox to Chrome due to its great extensibility. Also, even though Epichrome is great, it has problems like copying extensions for an SSB from one workstation to another. Firefox has no such problems; you can seamlessly copy settings, extensions, and everything from one machine to another since everything is neatly stored in a single profile folder.

According to Mozilla Wiki, there used to be a project called Prism which was an SSB for Firefox. It sounds quite nice, similar to Epichrome, and geared towards Firefox. Sadly, Mozilla dropped the project and the links which point to its alleged successor are all dead. So it seems that Prism is just dead. Is there anything like Prism for our modern day and age? I would prefer something that is free (i.e., gratis) and open-source would be nice, too.


1 Answer 1


This is an older question but for anyone still looking for a solution…

Starting with Firefox 77 you can enable SSB (site-specific browser) in the settings.

  1. Open about:config and look for the browser.ssb.enabled setting.
  2. Click the arrow to change the value to true and restart Firefox.
  3. Click the … next to the URL and choose "Use This Site in App Mode", you can also use the command line firefox --ssb https://example.com.
  • Whoops, exactly this is I looked for a little while. :-)
    – peterh
    Jun 15, 2020 at 14:18
  • Just a note that this feature has been removed from Firefox. They decided that not enough people used it to make it worth maintaining. bugzilla.mozilla.org/show_bug.cgi?id=1682593
    – flakshack
    May 20, 2021 at 0:37

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service and acknowledge you have read our privacy policy.

Not the answer you're looking for? Browse other questions tagged or ask your own question.