I have the need to overlay html content over streaming media.
I use a linux frame buffer with an RGBA8888 pixel format.
Normal widgets seem to work well, but when rendering a page with a transparent background, things break apart.

I have prepared a small test program to demonstrate the problem.
It c an be compiled on X11 (with a compositing window manager) where it shows the expected behaviour, that is the background of the page is transparent, and scrolling the contents up or down updates the page correctly 9 the tranparent pixels move around together with the opaque pixels).
When compiled and tested on the linuxfb device, the firs rendering looks right, but dragging the scrollbar around leaves the opaque text in place. After a few updates, the screen is full of black pixels.

To reproduce the problem:
compile the test program.
run the resulting executable, using the test page as an argument:

webkit-transparency-test testpage.html
or
webkit-transparency-test testpage.html -qws (on the embedded platform)

move around the scrollbar.