getfirebug.com has Firebug 1.6X.0a16, with a change the
maxVersion so Firebug will install in Firefox 4.0b1. Just to set expectations, some platform bugs scheduled for 4.0b2 will prevent Firebug from working completely on Firefox 4.0b1. I also was not able to run our test suite on 4.0b1 because the extensions we use for testing would not install even after the
maxVersion change was made. Nevertheless, we think most users will be successful with Firebug on Firefox 4.0b1 and we are keen to hear from the others ;-).
This release is dedicated to “tasoss” who manually tested Firebug 1.6 in all the Firefox 3.7 alpha builds for us. Thanks!
Fortunately this kind of work is no longer required. Jan ‘Honza’ Odvarko, Andrew Halberstadt, Clint Talbert, Rob Campbell and other folks at Mozilla on bug 559466 integrated Firefox and Firebug automated testing. The Firebug test suite now runs on both the security/stability branch of Firefox (currently 3.6.7) and the development or trunk branch (currently or at least tomorrow, 4.0b2). You can see the results in the getfirebug.com TestBot results page. (Well, actually what you will see is that the 4.0 tests failed altogether today because of the number change mentioned above; a few kinks remain ;-).
These automatic tests bring regressions or incompatible changes in the platform to everyone’s attention much sooner, so they can be addressed while the issues are still clear to the developers. After we get some experience with these tests, we may incorporate them in the platform checkin tests used to validate code changes.