629408 - [ff4b10 only] fading (changing the opacity using js), makes the background-color = black and not transparent

Status: RESOLVED DUPLICATE of bug 627393

(Core :: Graphics, defect)

Description

[AlfaOmega08]

User-Agent:       Mozilla/5.0 (Windows NT 6.1; WOW64; rv:2.0b10) Gecko/20100101 Firefox/4.0b10
Build Identifier: 

Any fadein/out js code, will produce this effect:
when opacity: 0, you see a black zone
when opacity: 1, you see it correctly
when opacity: 0.5, you see the element at 50% opaque, but behind it is black, you don't see what's under. This applies for any other value of opacity.

I tried using dojo and jQuery. If you just set opacity: 0.5, everything seems to be ok.

Reproducible: Always

Steps to Reproduce:
1. Create a webpage with a fading animation using JS
2. Open the page
3. Enjoy

or:
1. Open http://docs.dojocampus.org/dojo/fadeIn
2. Click any of the View Example buttons
3. Enjoy
Actual Results:  
You see a black element under the element being faded

Expected Results:  
To see what's under the element

Comment 1

[Xathien]

Attachment: Very simple test case

This changes the opacity on a div 3 times.

Comment 2

[Xathien]

Wish I could edit the post above...
Anyway, I have the same problem, I believe. Any time the opacity is changed on an element, it appears to revert to an opacity of 1 before re-rendering with the correct opacity. The test case above demonstrates it rather clearly, I think.

FWIW: Run on Win7 x64

Comment 3

[Boris Zbarsky [:bzbarsky]]

This works fine for me (though on Mac).

Do you still see this problem if you turn off hardware acceleration in preferences?

Comment 4

[Xathien]

Interesting. Turning off hardware acceleration immediately fixed the issue.

Comment 5

[Boris Zbarsky [:bzbarsky]]

Sounds like an accelerated layers issue...

Comment 6

[Robert O'Callahan (:roc) (email my personal email if necessary)]

Fixed on trunk? If so, dup of bug 627393.

Comment 7

[Joe Drew (not getting mail)]

I can reproduce this problem on Windows in beta 10, but not in the latest nightly.