I’m no longer running firefox trunk nightlies, having moved back to the 1.8 branch. It was nice having the new features, and I wish I could keep testing them, but the performance was just too bad. I was able to stand it for a long while, but then I had to test something on 1.8, and after that I just couldn’t go back. It’s amazing how a fast browser doesn’t seem all that much faster, but a slow one feels awful.
The perf bugs (mostly on Linux, from what I gather) have been sitting there untouched for a while, as people focused on the 1.8 branch, and went to XTech, and had vacations, and the like. Vlad says there will be work on them soon, though, within “the next few weeks” (on the 30th in mozilla.dev.tech.gfx). And indeed, one small fix went in yesterday, though not enough to make me switch back.
Hopefully “next few weeks” from the 30th turns out to mean starting at the end of this week and picking up next, so I don’t have to stay away too long.
Update: So it seems that that in fact, it wasn’t just psychological, there was a huge regression that happened on trunk while I was using branch. I’ve moved back to about half and half for now, because testing trunk is important and I know there aren’t enough people that do it, but I hope the cairo bugs get fixed soon.