I propose that at least one Sencha employee that uses the forums (to post as well as read) be shackled to a desk and forced to use Firefox. I really don't understand how the forums can have so many bugs in Firefox that go unfixed. I've documented some of them before, and about half of them were fixed. But the others sat untouched. And some of the bugs affect not only the forums but the entire Sencha website. I thought it was because I was still on the crusty FF 3.6 branch. But I finally bit the bullet and updated to the current FF and the problems remain.
I'm not going to detail the problems unless someone at Sencha promises that they'll actually try to fix them. But if you're committed to having your board software work under one of the most common browsers out there, I will have a go at it.
I would urge you to consider it a higher priority than currently. The forums are Sencha's public face, and it reflects poorly on the company when the Ext-ified interface works poorly.