问题
Recently my Firefox got updated to version 51.0.1. Initially it was showing some reminder check (I'm not clear with that) related to Firebug, but I ignored it. Now, the Firebug toolbar button is always shown deactivated.
I've reinstalled Firebug several times, but the result is always the same.
Is there any compatibility issue? How do I activate Firebug?
回答1:
There is a solution to use firebug [version 2.0.18] in latest version of firefox [this time 51.0.1]
To enable old Firebug
In address enter about:config, find
browser.tabs.remote.autostart set it false
browser.tabs.remote.autostart.1 set it false
browser.tabs.remote.autostart.2 set it false
回答2:
This is the new version of FF and it is not working as intended and making life of developers & designers even more difficult... look at review https://addons.mozilla.org/en-US/firefox/addon/firebug/reviews/?page=1.
This actually is FireFox DevTools as FB is no longer supported for future developments
You can install the previous version to work with, I installed it and my problem is solved i have my old version back.. https://addons.mozilla.org/en-US/firefox/addon/firebug/versions/.
New version of comes with some new features but some handy features are also left out. It looks totally new to me. May be one day i have to get used to it. For now one can revert back to old version
回答3:
This is because Firebug is integrated into the Firefox DevTools once multi-process Firefox is enabled and it doesn't track the enabled state of those tools. This is a known bug.
Note that a click on the Firebug button with multi-process Firefox enabled actually opens the Firefox DevTools with a Firebug theme trying to make the transition a bit easier, because Firebug is officially discontinued.
If you want the old Firebug back and by that make the Firebug button work again as expected, you need to disabled multi-process Firefox as explained in an answer to a similar question by going to about:config and setting the preferences browser.tabs.remote.autostart, browser.tabs.remote.autostart.1 and browser.tabs.remote.autostart.2 to false. Though note that this is just a temporary workaround, because multi-process Firefox will be mandatory at some point.
Furthermore, the Firefox DevTools offer a lot more features than Firebug but are also lacking some Firebug had. Therefore, a bug is filed to close those gaps.
In the answer to a related question I've listed what your alternatives are.
If you want to stay with the Firefox DevTools, there is a migration guide for Firebug users.
回答4:
Firebug seems to have activated for me after I got the Web Developer Add-On on Firefox, link: https://addons.mozilla.org/en-us/firefox/addon/web-developer/
回答5:
Open the default Element Inspector, and click settings icon
Under the Themes section you will see Light option is checked and change it ot Firebug automatically Firebug will activated.
回答6:
The best way to install firepath and firebug to downgrade firefox by downloading older version of firefox like 31 from firefox ftp.
I downloaded older version of firefox from http://mozilla_firefox.en.downloadastro.com/old_versions/
After downgrading go to option-> Update and check "Never check for updates" checkbox
If the below setting has been made:
In address enter about:config, find
browser.tabs.remote.autostart set it false
browser.tabs.remote.autostart.1 set it false
browser.tabs.remote.autostart.2 set it false
Then reset firefox by typing 'about:support' in the address bar
Click "reset firefox"
By doing this you should be able to install firepath, firebug addons from the mozilla addons page
来源：https://stackoverflow.com/questions/41929647/firebug-toolbar-button-is-always-shown-deactivated-since-firefox-51-0-1