Re: Problem on implementing ::backdrop pseudo-element

On Mon, Nov 2, 2015 at 9:50 PM, Robert O'Callahan <[email protected]> wrote:
> On Mon, Nov 2, 2015 at 6:58 PM, Xidorn Quan <[email protected]> wrote:
>>
>> However, ::backdrop cannot be implemented that way, becasue any
>> element can go fullscreen, which means the frame of the fullscreen
>> element can be video, image, or iframe. Those frame are not container
>> frame, and thus cannot be a parent frame.
>
>
> nsVideoFrame is a container frame.
>
> How about we make nsImageFrame and nsSubdocumentFrame inherit from
> nsContainerFrame?

Well, any HTML element can enter fullscreen. Does that mean we would
make all possible frame inherit from nsContainerFrame?

Hmmm, it seems most of them already have been. The left ones, as far
as I can see, are: image, subdocument, form control, and br. (It seems
table col does not become a normal block as expected. I'll have a look
at it.) Do we want all of them to inherit from nsContainerFrame?

It looks like the easiest approach. I'm not quite comfortable with it,
though. FWIW that would bloat those frames by four pointers.

- Xidorn