It’s necessary to download the add-on as an .xpi file (ignoring the warning from Mozilla that Firefox is required), then add it as indicated in the above screenshot. I tried to add NoScript, but unfortunately attempting to enable it results in freezing, then crashing of Web on my laptop (running the latest Linux Mint). Relaunching results in a crash every time as well. I finally had to use dconf Editor to remove the add-on and restore functionality.
I don’t recall ever seeing the “ability” to use Firefox extensions in Web. (This is version 46.0.) Has anybody got this to work?
Due to its weaker privacy profile, I use Web only occasionally, and only for a few websites that won’t play nice with LibreWolf or Firefox.
I pointed Epiphany at an existing .xpi file (click + as per your screenshot, click Downloads where the .xpi file is, click the .xpi file, click Open) and it does nothing. However the .xpi file did get copied to the appropriate folder. Further investigation … on restarting Epiphany it gives
Failed to load extension <path>: Only manifest_version 2 is supported
So, OK, that is an additional constraint on testing - and suggestive of immature code, not really ready for primetime.
Fortunately vi has full support for .xpi files etc. - so easy to verify that the extension that I was testing with uses manifest_version 3 - oh well off to see whether there’s another extension that I would like to try.
Trying another one … installs, doesn’t crash the browser, but doesn’t exactly work either. Gives
Emitting in view errored: undefined:1:15: TypeError: undefined is not an object (evaluating 'window.browser.runtime')
