Does anyone know of any harm in hiding flash elements that collide with an overlaying DIV? By hiding I mean setting the css visibility to hidden.
I understand that it requires a DOM traversal to look for objects and embeds which causes some overhead, but are there any other reasons why people don't do this?
This is for sites that don't change their flash wmode to transparent.
For a long time, browsers on Linux could not layer Flash. The transparent wmode was not supported, so many Flash animations were enclosed in gray boxes. Any Flash in background layers would render on top of foreground content. This made many sites frustrating and unusable, particularly those with peelback ads and Flash backgrounds.
This was fixed in Ubuntu only recently, within the past 12 months.
Sounds like you're creating an overlay onto pages that you don't control? If you're using a DOM traversal to find an embedded SWF object, you should be able to use the SWFObject javascript library to register that SWF, then you can set the wmode value to "transparent". Then you won't have to hide the Flash and your floating element will appear correctly. The only problem may be that the SWF might look weird since setting wmode to transparent will remove the stage background color, if any.