Scrolling Behavior in 3.1b1?

anaesthetica

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Oct 15, 2008, 10:12:52 AM10/15/08

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Dear Firefox folks,

I've downloaded the new Firefox 3.1b1 and it seems to me that the
scrolling behavior has changed since 3.0. When I scroll using the two-
finger trackpad gesture on OS X, Firefox 3.1b1 will often continue to
scroll for half a second after I stop moving my fingers. This was not
the case on 3.0. Have there been any deliberate changes to the
scrolling behavior between versions?

My setup is:
- Mac OS X 10.5.5
- Firefox 3.1b1
- MacBook Pro

Thanks for your time,

Tom

Markus Stange

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Oct 15, 2008, 10:41:13 AM10/15/08

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Hi Tom,

On 15.10.2008 16:12 Uhr, anaesthetica wrote:
> I've downloaded the new Firefox 3.1b1 and it seems to me that the
> scrolling behavior has changed since 3.0. When I scroll using the two-
> finger trackpad gesture on OS X, Firefox 3.1b1 will often continue to
> scroll for half a second after I stop moving my fingers. This was not
> the case on 3.0. Have there been any deliberate changes to the
> scrolling behavior between versions?

Yes, there was a change: the precision of touchpad scrolling has
increased. We now support pixel scrolling [1], which is much smoother
than the previous line scrolling.

The lag you're experiencing is an unfortunate side-effect of pixel
scrolling, and we're not sure yet if there's a way to fix it for Firefox
3.1 (see bug 418351 [2]).
Robert O'Callahan is working on an architectural change called
"Compositor" which will probably be necessary to fix the responsiveness
problem. Unfortunately, Compositor won't make it into Firefox 3.1.

In about:config, you can set the "mousewheel.enable_pixel_scrolling"
preference to false in order to turn off pixel scrolling.

Hope this helps,
Markus

[1] https://bugzilla.mozilla.org/show_bug.cgi?id=350471
[2] https://bugzilla.mozilla.org/show_bug.cgi?id=418351

anaesthetica

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Oct 15, 2008, 10:49:04 AM10/15/08

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Markus,

Thanks so much for the quick response. That solved my problem right
away.

Best,

Tom

Markus Stange

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Oct 16, 2008, 10:05:00 AM10/16/08

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Hi Tom,

could you try if this build fixes the problem for you?
http://tests.themasta.com/fastscrolling_firefox-3.1b2pre.en-US.mac.dmg

It contains the patches for bug 459319 and bug 457864.

Cheers,
Markus

anaesthetica

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Oct 17, 2008, 1:57:40 AM10/17/08

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Markus,

I'm happy to report that after downloading Minefield and resetting
mousewheel.enable_pixel_scrolling to "true", the scrolling issue seems
to have been cleared up.

Thanks so much for following up on this with me.

All the best,

Tom

On Oct 16, 10:05 am, Markus Stange <msta...@themasta.com> wrote:
> Hi Tom,
>

> could you try if this build fixes the problem for you?http://tests.themasta.com/fastscrolling_firefox-3.1b2pre.en-US.mac.dmg

1compu...@gmail.com

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Oct 20, 2008, 10:12:13 PM10/20/08

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I notice the exact same behavior, and wish I could disable it in
about:config but cant seem to find the option. Anyone know?

Markus Stange

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Oct 24, 2008, 4:22:48 AM10/24/08

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On 21.10.2008 4:12 Uhr, 1compu...@gmail.com wrote:
> I notice the exact same behavior, and wish I could disable it in
> about:config but cant seem to find the option.

Are you using 3.1 Beta 1?