642398 - Scrolling over Flash Video stuttering at max viewport (only when dock visible) FF4 RC @ Mac OSX 10.6.6 13"

Status: RESOLVED INCOMPLETE

(Core :: Graphics, defect)

Description

[Martin Peter]

User-Agent:       Mozilla/5.0 (Macintosh; Intel Mac OS X 10.6; rv:2.0) Gecko/20100101 Firefox/4.0
Build Identifier: Mozilla/5.0 (Macintosh; Intel Mac OS X 10.6; rv:2.0) Gecko/20100101 Firefox/4.0

The problem appears to be significant, when the viewport has it's maximum vertical size and the Mac Dock is visible. "Maximum vertical size" means: Resize the window manually by pulling it vertically down, till you can't go further (because of dock).

The problem disappears if you do one of the following things:

1. resize the viewport vertically (even if it is 1px) to something smaller than vertical maximum.
2. Enable full screen
3. Hide Dock


Reproducible: Always

Steps to Reproduce:
1. Start FF4 RC on latest Mac OSX 10.6.6
2. Make sure dock is visible
3. resize/pull the ff window to it's max. vertcal size (till dock is reached)
4. Go to http://www.golem.de/1103/82143.html and start scrolling down
Actual Results:  
You should now experience the stuttering, when scrolling over the flash elements. I'm trying on a brandnew MacBookPro 13" (2011 model).

Expected Results:  
Not stutter, perform smooth scrolling

The problem disappears if you do one of the following things:

1. resize the viewport vertically (even if it is 1px) to something smaller than vertical maximum.
2. Enable full screen
3. Hide Dock

Comment 1

[Martin Peter]

Little correction: It's not one 1px you have to resize the viewport, to make the problem disappear, but approximately 5px.

Comment 2

[Thorsten Gebuhr]

Can reproduce this stuttering scrolling also on Win7 64bit - no matter if the browser is fullscreen, taskmanager visible or not...

You need a flash-video of larger size (e.g. YouTube)as long as it is in the visible area scrolling becomes stuttering.

Switching to WebM on YouTube solved the scrolling-issue - seems to be related to the flash-area (Shockwave Flash 10.2 r152).

The competition (Chrome, IE9) scroll smoothly here.

Comment 3

[Martin Peter]

One additional observation:

When skype shows a notification (e.g. someone logging in), the scrolling is affected again, although i scaled the viewport to a size, where the problem used to dissapear. (I'm using the internal notification system of skype, not growl).

Obviously there is a problem with transparent, touching (dock) and overlaying (notification) elements with FF4RC.

Comment 4

[u597032]

Flash is no longer supported