It's not possible to activate the DevEdition theme on Release. Apparently a bunch of folks were using the DevEdition theme on Release by toggling browser.devedition.theme.enabled in about:config, and now that we've switched how the theme is included, that pref is ignored. The resources still appear to be present, e.g., resource:///chrome/browser/content/browser/defaultthemes/devedition.icon.png, but we don't have a path for these folks to actually toggle the theme. Would it be possible to add a pref or workaround for these users? Reddit comments with folks looking for its return: https://www.reddit.com/r/firefox/comments/3gm945/is_it_possible_to_activate_devedition_theme_in/ CC'ing :bgrins since he might have context.
This has been discussed in Bug 1181721 which was WONTFIXed: > I think we should WONTFIX this. The DevTheme is intended as a visually > distinct theme for devtools, and that's where development focus is. If > someone wants to spin it off into a separate heavyweight / lightweight theme > on AMO, that's fine. (Or just use one of the existing darkish themes there) > > Otherwise, this effectively becomes "add and support a dark and light theme > to stock Firefox", and I don't think that's something we want to do given > current priorities. It's unfortunate that the feature was available through a pref so that we ended up removing a feature when refactoring this to work with the lightweight theme manager. I think we should come up with some way to still support it though.. let's move the discussion to 1181721