YSlow won’t work with Fire Fox 9 because it requires Firebug to work. And the latest versions of Firebug, 1.8, 1.9, and 1.10, do not work with YSlow. Until Yahoo gets around to updating their plugin, use this method to make YSlow work with your Firefox.
You may want to backup your profile before doing this – instructions are provided at the end of the posting.
Type in `about:config` into your address bar. After accepting the “this is dangerous” message right click and create a new entry. Make sure it is a BOOL.
Set the name to:
extensions.checkCompatibility.9.0
and then set the value to `false`
Now visit http://getfirebug.com/releases/firebug/1.7X/ and click on the latest version of Firebug 1.7, which I believe is `firebug-1.7X.0b4.xpi`
I’m assuming that you already have YSlow installed – but if you don’t then install it too.
Restart Firefox. Voila! Now your YSlow is working again! Feel free to leave a comment to thank me or suggest any tips or tricks related to YSlow and Firefox :)
You can either keep using Firebug 1.7 but if it’s really bothering you go ahead and reinstall the latest Firebug and then create a separate profile to use with YSlow.
See Mozilla’s notes on using separate profiles: http://kb.mozillazine.org/Profile_manager
