User-Agent: Mozilla/5.0 (Macintosh; U; PPC Mac OS X 10.4; en-US; rv:1.9) Gecko/2008061004 Firefox/3.0 Build Identifier: Mozilla/5.0 (Macintosh; U; PPC Mac OS X 10.4; en-US; rv:1.9) Gecko/2008061004 Firefox/3.0 On this specific page, if I click in the open area of the scrollbar to scroll down (or up) the page jumps down two or three page increments, as if my click on the scrollbar is registering more than once. Reproducible: Always Steps to Reproduce: 1. Load page. 2. Click in scrollbar below thumb. Actual Results: View jumps down two or three screen lengths, one at a time. Expected Results: View jumps down one screen length. I have only encountered this on the specific web site involved, but on that website the problem does not appear in Safari. The problem DOES occur with JavaScript turned off (using Web Developer extension to disable all JavaScript), so it looks like it's not something in one of the page scripts. If you click on a part of the scrollbar such that the thumb will be under your mouse after a single jump down, the jump down will not repeat. That is, if you click immediately under the thumb, it will jump one page increment and stop. This is why I believe that the issue involves the click registering multiple times.

I was able to reproduce what you report with FF3 on OS X 10.4.11, though not with FF2, and not with either FF2 or FF3 on OS X 10.5.3. But then I gave myself a fresh profile, and now I'm not able to reproduce it on OS X 10.4.11, either. What I did to give myself a fresh profile was to quit Firefox, then rename the Firefox directory under ~/Library/Application Support/ to Firefox.old, then restart Firefox. It's conceivable that going back and forth between FF2 and FF3 (something I often do in testing) caused some kind of minor corruption in my profile. I've no idea why I only saw the problem on OS X 10.4.11. Please try giving yourself a fresh profile and let us know your results.

Sorry it's taken me so long to follow up on this. I have been using OS X 10.4.11--I do not yet have 10.5. I gave myself a fresh profile and I still encountered the problem. It seems as if it is sensitive to how long the mouse button is held down when I click. If I try very hard to make the fastest click possible, it often scrolls only one increment. But if I'm slightly slower--but well within the realm of a normal click rather than any sort of "click-and-hold"--it registers multiple times.

I went to the site/page that was having the problem and downloaded the page and the CSS file it was using. I spent some time stripping both down to the absolute minimum necessary to still have the scrolling issue exist. This attachment is a single HTML file that contains the style declaration and a table of text that produces the scrolling problem. What remains: (1) a table with one row and two columns, with the first column full of text and the second column empty. (2) The table has a style with border-collapse set to collapse (3) An ID selector gives the second column of the table a 1-pixed dotted border. It seems as if the problem is more pronounced when there is more text present, so I left a good deal of text in the first column.

Each time I've tried FF3 I've encountered this problem on OS X 10.4.11 and then backed off to FF2. I'm on an iBook G3 so OS X 10.5 is not possible. I encounter the problem on any web page with a large number of screens (slider less than 10% of scroll bar). I use only the iBook touchpad. I've tried it both with and without tapping activated. I really would like to get to FF3 but this behavior is too irritating for me.

I'm using latest version 3.5.2, I have this problem and it's very very annoying. when I click, it 90% time will scroll down 2 pages, and only very few times it will scroll correctly. scroll up is better, most time scroll up 1 page, a few times it scrolls up 2 pages too.

by the way, I'm using it on windows 2000.