I just realized my information might be misleading. To clarify, the Firebug button is still there even when the multiprocess functionality is enabled. Though, instead of opening Firebug, it opens the Firefox DevTools with a Firebug theme.
Having said that, the *Inspect Element with Firebug* option should be hidden <https://github.com/firebug/firebug/commit/8c0f43d827a3b7e732a253757390af1ceb68d2b4> in Firebug 2.0.19 when the multiprocess feature is enabled. It it looks like it is somehow not enabled for you even with the aforementioned preference set to true. Btw. it is normal that the status of that preference says *user set*. User set actually means "changed", because Mozilla is switching that preference gradually for more and more users with every release. I.e. the default value is still false, though it gets set to true by browser updates. Sebastian On Thursday, June 8, 2017 at 2:18:44 PM UTC+2, L wrote: > > Hi Sebastian, > > Thank you for the explanation, however, browser.tabs.remote.autostart.2 > is set to *true*, rather than false as you suggest. Status = *user set*, > but I did not change this manually or install/modify any add ons recently > (for quite a long time actually). Additionally none of my other active > add-ons were updated since Jan 2017 and Firebug was missing after this > time. Firebug itself was last updated Mar 1, 2017, but I expect it did not > make the change itself since it has accepted its fate (also I am pretty > sure it was missing after March since I only recently noticed its > resurrection). > > I do notice that Adblock Plus, which I have had disabled for years, states > that it was last updated June 7, 2017. Are disabled add-ons updated > automatically and can they change settings? > > A bit of a mystery. Sorry to cause alarm. I did not realise the > multiprocess function could be controlled via the configuration because I > recall seeing a compatibility version of Firefox, which I understood to be > for this purpose. > > Thank you again and for providing the useful links. > > L > > On Wednesday, June 7, 2017 at 10:00:36 PM UTC+1, Sebastian Zartner wrote: >> >> That you see *Inspect Element with Firebug* again means that the >> preference browser.tabs.remote.autostart.2 is set to false for you. See >> my related answer on Stack Overflow >> <https://stackoverflow.com/a/40748127/432681>. >> As far as I know, this doesn't happen by itself, so it might be that it >> happened with an update of Firefox or another add-on or you turned off >> multiprocess >> Firefox <https://developer.mozilla.org/de/Firefox/Multiprocess_Firefox> >> manually. >> >> Please note that Firebug will definitely stop working once Firefox 57 is >> released, which will happen in November this year. With that version Firefox >> restricts its add-on support to WebExtensions >> <https://blog.mozilla.org/addons/2016/11/23/add-ons-in-2017/> - and >> Firebug is based on another (then incompatible) technology. >> >> So, you're definitely better off getting used to the Firefox DevTools >> <https://developer.mozilla.org/en-US/docs/Tools/> already. I've written >> a migration guide >> <https://developer.mozilla.org/en-US/docs/Tools/Migrating_from_Firebug> >> some time ago to make the live of Firebug users a little easier. >> >> Sebastian >> >> On Wednesday, June 7, 2017 at 2:29:20 PM UTC+2, L wrote: >>> >>> "Inspect Element with Firebug" is back in the context menu (and so is >>> the icon up above) and low and behold it works :-) >>> >>> What is going on and why is the internet not raving about this blessed >>> news? Or is this just a blip? >>> >>> I know there was a way to continue using Firebug by installing a >>> compatibility version of Firefox, but I did not do this, accepting that I >>> would at some point have to get used to the new tool anyway. >>> >>> Eagerly awaiting news, >>> >>> L >>> >> -- You received this message because you are subscribed to the Google Groups "Firebug" group. To unsubscribe from this group and stop receiving emails from it, send an email to firebug+unsubscr...@googlegroups.com. To post to this group, send email to firebug@googlegroups.com. Visit this group at https://groups.google.com/group/firebug. To view this discussion on the web visit https://groups.google.com/d/msgid/firebug/42e93b71-b217-4421-b45b-d4666e2af8c3%40googlegroups.com. For more options, visit https://groups.google.com/d/optout.