591020 - Flash + Scroll down = messes up Cursor aim on Flash applications

Status: RESOLVED WORKSFORME

(Firefox :: General, defect)

Description

[matthewto12]

User-Agent:       Mozilla/5.0 (Windows NT 6.0; rv:2.0b4) Gecko/20100818 Firefox/4.0b4
Build Identifier: Mozilla/5.0 (Windows NT 6.0; rv:2.0b4) Gecko/20100818 Firefox/4.0b4

Let's say there's a Flash application on the web page. You scroll down, and you try to click on a button in the Flash application. It will not register on where you try to click, but instead it will register where you click if the page was scrolled to the top.

Reproducible: Always

Steps to Reproduce:
1. Go to a website with Flash (and buttons to click in Flash)
2. Scroll down (page must be able to scroll down)
3. Try to click a button and it will not aim properly to the button you try to click
Actual Results:  
Failure to click on something I want (ex. Flash Button) unless I was on top of the web page. (must be Flash)

Expected Results:  
Be able to click Flash buttons in Flash applications in a web page precisely instead of aiming at somewhere else of a large Flash application.

Ex.
Imagine a Flash-created Box, with a button on the bottom of the Flash Box.
You scroll down and you try to click the button on the near-bottom of the Flash Box.
The click registers in the middle of the Flash Box instead of the button on the bottom of the Flash Box.
That is what I mean.
Please fix as it can affect people who use Flash. YouTube is not affected.
The more you have to scroll, the worse it gets, if the button is at the very bottom and you scrolled down quite a bit, you may not be able to click it unless you scroll to the very top.

I can produce a small video if you do not understand what I mean (which I am quite unclear about).

Comment 1

[jag (Peter Annema)]

I can confirm this. Easy steps to reproduce (be sure not to switch away from that tab / window while testing, and adjust the height of your browser as needed):

1. Go to http://www.adobe.com/software/flash/about/
2a. Once the flash content has loaded, hover over "Install Now"
2b. Confirm that you get hover effects and hand cursor
3a. Scroll the page, then hover over "Install Now"
3b. Notice that you don't get hover effects nor hand cursor

Similarly you can't click the button after scrolling.

If you scroll the page back, or if you switch to another tab or window and then back, hovering over the button once again works as expected.

If for step 3a you scroll the page just a few pixels (e.g. by clicking the down arrow on the scroll bar) you'll notice that the top of the button doesn't respond to the mouse, while the bit of blue below the button now seems to be part of the it. It's like no one told the button (or rather, the plugin) that it got moved.

I suspect that after scrolling we're not updating the translation of Fx's coordinate system to Flash's. Losing and regaining focus updates things. I also don't think this is Flash specific, but affects all plugins.

Comment 3

[jag (Peter Annema)]

I bet there's a bug with more action on this already. Gonna dig through bugzilla a bit more.

Comment 4

[jag (Peter Annema)]

I just reproduced this with OOPP turned off (dom.ipc.plugins.enabled=false), on Win XP with 4b6.

Silverlight (test at e.g. http://www.silverlight.net/showcase/) seems to have a similar problem, though it seems to be confused about the offset even before scrolling. Switching tabs/windows doesn't seem to reset things though.

Comment 5

[jag (Peter Annema)]

Hrm, Google Earth doesn't seem to have the problem, so it could be just Flash, and Silverlight's problem(s) could be a different bug.

Comment 6

[Jim Mathies [:jimm]]

(In reply to comment #4)
> I just reproduced this with OOPP turned off (dom.ipc.plugins.enabled=false), on
> Win XP with 4b6.
> 
> Silverlight (test at e.g. http://www.silverlight.net/showcase/) seems to have a
> similar problem, though it seems to be confused about the offset even before
> scrolling. Switching tabs/windows doesn't seem to reset things though.

I would treat sl and flash separately. (Sl has a cursor position problem in the 3.0 version that is fixed in the 4.0 version fx 4.0.)

Comment 7

[jag (Peter Annema)]

This works for me now in a recent Firefox and Flash (Fx 4.0b11, Flash 10.2 release).

Please reopen if it's still a problem.