I have been putting this off for a few years. To cleanup the removed-files.in Firefox will need to have to update to a build that has the patch from bug 386760 which landed for Firefox 5. When we stopped supporting Win XP SP1 and below we required Windows users to update to Firefox 12 before updating to a newer release so we could get the service pack info in the update url which was implemented in bug 668436. I propose that we do essentially the same thing we did for Mac and Linux as we did for Windows by adding a requirement for Mac and Linux Firefox before Firefox 5 (without the patch from bug 386760) to first update to Firefox 12 (with the patch from 386760). Note: I chose Firefox 12 since we already have a requirement for Windows users to update to Firefox 12 and it could just as easily be any version that includes the patch from bug 386760.

Per :nthomas every release 9.0.1 and prior - updates to 12.0 on all platforms, before getting anything newer. I'll allow you or him to resolve this or claim otherwise though

I recall discussing only doing this for Windows way back when... if it is all platforms then I'm good to go and this bug can be resolved.

I put this up in graphical form at http://people.mozilla.com/~nthomas/update-watch/release/old-release.html which was generated just now. Due to the way the tooling worked it was always simpler to treat all platforms the same, and everything old goes through 12 (possibly in multiple hops before then).

Thanks!