Allow configuration of the user agent automatically on a per-domain basis

[keithbowes]

This should be easy to accomplish by writing the general.useragent.site_specific_overrides and general.useragent.override.[sitename] prefs. The hard part will likely be designing the front-end to manage them.

[razron]

Have no idea if it would help you may want to look at UAControl : [ https://addons.mozilla.org/en-us/firefox/addon/uacontrol/ ].

[keithbowes]

I've never tried UAControl, but I was looking at the UI in Konqueror as inspiration. Anyway, I've abandoned doing it this way. I'm going to wait for the migration to WebExtensions and filter in the WebRequest callback, without messing with the user's browser settings.