Feedback on Scrolling Changes for Windows

The acceleration based scrolling model on Windows has been landed in the nightly builds for a little over a week now, so I wanted to get a post up for people to provide feedback on how well they think the current implementation is working, now that everyone has had some time to acclimate to the change.

Caveat: One really significant issue we are working on is correctly handling the case where the user already has an acceleration model being provided by their mouse or mouse driver, in which case adding another one is obviously really problematic. If you are finding scrolling to be a bit out of control at the moment, you may be encountering double acceleration.


  1. Yeah, I found the double acceleration annoying when I used the touchpad on my laptop, and with a mouse, I sometimes overshot what I was looking for, leaving me to actually scroll slower than I normally would

  2. I have standard MS Mouse, using Vista’s default driver, and this new scrolling behaviour is out of control – a turn of the mousewheel as I’m reading a page scrolls me *way* past the next few lines.

    There’s obviously something majorly, majorly wrong with this patch and I urge you to back it out until it can be fixed.

    For the record, I don’t have this problem with Chrome.

  3. I’m in exactly the same situation as Doug. I never noticed a problem with Firefox 3.5’s scrolling because I have a MS mouse with a built-in acceleration feature. I tried the Firefox 3.6 alpha and scrolling was completely messed up – it would scroll either way to fast or way to slow. I’m not sure what can be done to fix this, apart from not including the accelerated scrolling feature. How do other browsers handle this?

  4. I tried the new settings for a few days, but I couldn’t get used to it (I don’t have a mouse with acceleration).

    First the change in the number of lines scrolled when you roll the wheel one notch: I’m so used to the default of 3 lines, that having this doubled is quite disturbing when you are reading a page (in this case you don’t need acceleration because you scroll very slowly).

    Then I think the acceleration settings are too sensitive. When you just want to scroll down a page, you find yourself having scrolled way more than you wanted. I’m currently using mousewheel.acceleration.factor/start of 5/5 (instead of 10/3) and that seems to work well for me.

  5. I hated it at first but am getting used to it–not sure that I really like it though. One mouse wheel scroll goes down about 4 lines on your 1.5(?) spaced “Caveat … acceleration.” paragraph. I doubt it’s a double acceleration problem and it’s more about getting used to it. Having a mouse wheel I can repeatedly rub my finger over means if it’s slow I just move more quickly and adjust with my own speed rather than needing browser based acceleration but I imagine it may be different for other scrolling models. For the record my factor/start is 10/3.

    I’m not sure why Doug thinks it should be backed out since it’s easy enough to change in about:config and hopefully you will fix any doubling. But, I think this is a matter of personal preference in the end so you should set default to what the majority of users want and let the rest change it.

  6. Hi, I am using a Logitech G5 refresh with Setpoint 4.7 which doesn’t allow mouse wheel acceleration afaik (other Logitech mice do tho, like the MX Revolution, where this feature is built in no matter if Setpoint is installed or not). When I tried 3.7a1pre I wasn’t sure if the new mouse wheel acceleration was working but when I compared it with 3.5 I knew it was. It felt really good. It wasn’t too much but it was enough to go to the bottom of a mid-sized page with striking my mouse wheel only once. I was still able to navigate precisely when using it slowly. So I guess thats how its supposed to be working, again, I like it. :)

  7. I bought a Logitech M505 wireless notebook laser mouse yesterday, and the scrolling in the latest nightly of Firefox 3.6 is much better (at least it is no longer erratic like it was with my Microsoft mouse). It still seems like the accelerated scrolling could use some tweaks, though. It is hard to scroll quickly to where I want to. I don’t know, maybe I just need time to get used to it.

  8. Artem S. Tashkinov

    With this patch scrolling in Linux has become insanely fast.

  9. It’s too fast. At first I was impressed with the speed at which things were moving, but that wore off quickly when I tried to read text! It seems like this is the kind of thing that should be able to be toggled on and off, like the caret browsing… and this is more useful than caret browsing IMO. If I could hit F? and scroll super fast through a long blog and hit it again to read the article, that would be sweet.

  10. I have no issue with an accelerated scrolling system in principle (although I do feel it might be better done by the OS, but more technical people can debate that). However I do feel that the accelerated speed – i.e. the number of lines scrolled from one wheel notch – is far too high in 3.6 beta 1.

    That’s opinion. Something else that may be a bug is that while that holds true on most sites, Google Reader is far *slower* scrolling than it was in 3.5. Not enough of a web techie to guess at reasons, I’m afraid.