WebDeveloper add-on for Firefox 3.* (all betas and stuff)
Update: Web Developer addon now officially supports Firefox 3. Check out history (version 1.1.5). Download the new version here.
Old post about my hack:
Just a note that there are a number of features that do not work correctly in Firefox 3. I am working on fixing these and putting together a new release. You are free to use this hacked version of course, but just a word of warning.
Today I tried out the brand new Firefox 3 Beta 2. Nice. I like the new address bar and the ability to resume downloads after closing Firefox. The only thing I needed was WebDeveloper add-on (extension), which, unfortunately, does not work in FF3 yet. So, since I had a bit of add-on development experience I decided to change the max version inside the add-on. No problems occurred. Grab the .xpi (change file extension from "jpg" to "xpi" and open it with FF): 
That is all 
January 16th, 2008 - 16:33
Yes, thkx for taking the effort
January 16th, 2008 - 23:05
You’re welcome
January 19th, 2008 - 18:43
Thanks for this version of plugin!
January 22nd, 2008 - 05:41
The link (after changing to xpi) is a 404.
January 22nd, 2008 - 15:40
The thing is that you first download the file. And only after that you change the extension to xpi.
Hope this helps.
January 25th, 2008 - 18:47
Just a note that there are a number of features that do not work correctly in Firefox 3. I am working on fixing these and putting together a new release. You are free to use this hacked version of course, but just a word of warning.
Chris Pederick – Author of Web Developer
January 26th, 2008 - 14:07
Hey, Chris. Very nice to see you here. I hope you don’t mind that I changed the add-on’s max version. I’ve put your words into the post so that people can see them.
February 5th, 2008 - 01:15
Thank you!
February 14th, 2008 - 20:50
Thanks for this. I was a little skeptical about renaming the file and it’s safety, but after doing a recursive diff on the files against the originals, it’s legit. Thanks again for putting this together!
February 15th, 2008 - 04:13
Applause
February 15th, 2008 - 09:37
Patryk, suspicious, huh?
That is good. I guess I should explain a bit – WordPress simply does not allow uploading files with extensions other than pictures or documents. *.xpi files, for example, are not allowed. So I had to change the extension to something WordPress would accept.
February 18th, 2008 - 21:00
Well, that makes complete sense then. I’m going to try your hack on the other plugins I use until they’re patched/updated properly. Hopefully I’ll have similar results. Thanks again; The dev team I work on would love to use FF3 with their plugins. We got exited when I came across this page.
February 22nd, 2008 - 12:28
I am happy to hear that. And, yes, one could do that with any Firefox addon. That doesn’t mean that the addon will work correctly with FF3. It only means that Firefox will allow users to install it.
Anyway, good luck.
March 2nd, 2008 - 19:41
Hack for FireFox 3 Beta 3? I haven’t developed any extensions, would I be able to change the version number?
March 3rd, 2008 - 18:54
This version should work with beta 3 too. The max version is 3.*
March 4th, 2008 - 19:12
Hey great, just what I needed!!
I just found another solution: http://lifehacker.com/355973/make-your-extensions-work-with-the-firefox-3-beta
March 13th, 2008 - 14:23
THANK YOU! THANK YOU! THANK YOU!!
May 19th, 2008 - 11:31
It looks like the web developer toolbar no longer works with FF3 as of RC1