Comment 254 for bug 125970

I guess I'm not really surprised that this is still open, and I'm even less surprised that it's gotten so confused in comments.

I wonder if it wouldn't be more helpful to open a new bug that targets this problem very specifically and doesn't have 5 years of confusion hampering it?

In any case, I'll try to summarize the problems that have been brought up and their status as far as I know:

1. Performance is worse when a page has fixed ELEMENTS (i.e. not a fixed background). Performance decreases as the number of fixed elements grows. I believe this is still an issue and will include my evidence in the following comment.

2. Performance was worse when a page has the background-attachment: fixed CSS property applied. This problem is bug 90198. It is AFAIK totally unrelated to the current bug, and it seems that it doesn't generally affect people anymore.

3. On Windows, performance was worse when other windows were on top of the Firefox viewport. This seems to have been fixed since comment 24.

4. I think there's a problem where having opened enough images, pages, or other applications causes a sudden and drastic drop in scrolling performance (see bug 90198 comment 21). This is what I was talking about in comment 6, and haven't since been able to reproduce. It is NOT this bug.

5. Any slow/CPU-intensive scrolling is more so with smooth scrolling enabled. This is either common sense or a different bug, depending on your viewpoint.

6. Slow scrolling with large tables is bug 421601 and is totally unrelated, except that they can be used to emphasize the perf difference between a page w/ and w/o fixed elements.

7. Slow scrolling with resized images is bug 163975 and is totally unrelated, except that it can be used to emphasize the perf difference between a page w/ and w/o fixed elements.

Did I miss anything?

If we're going to leave this open, let's just focus on THIS bug and stop getting hung up on the other things that exacerbate it.