Xidorn Quan

It sounds like a browser bug that it fires `fullscreenchange` for fullscreen mode.

> Is that the reason for the current behavior? Yes. CSS variables are propagated via inheritance into descendants, so if a pseudo-element doesn't inherit from anything, CSS variables which are...

I wonder why was it made not inherit anything? If there isn't really any compelling reason, I guess we should probably just have it inherit from the element.

> There wasn't a compelling reason. As I said in the other issue it was to address https://lists.w3.org/Archives/Public/www-style/2012Jun/0441.html and back then we didn't have CSS variables. OK. I guess that...

How an element/pseudo-element is rendered has no effect on where it inherits from. It's only a question of where is the element/pseudo-element logically located in the DOM tree. e.g., `::before`...

I don't think it makes much sense to distinguish between variables and other properties. That may add implementation complexity for no good reason.

I guess this needs an email to the CSSWG. And also, it seems there is a typo in the spec which says [`perspective(0)` is a "Neutral element for addition"](https://drafts.csswg.org/css-transforms/#neutral-element).

Firefox clamps 0 to the smallest non-zero float value as suggested by Tab.

Note that fullscreen root doesn't have a visible `::backdrop` pseudo-element, so it doesn't matter whether the background is propagated.

Also note that a fullscreen body won't have the document level scrollbar because it is in general just a normal block element. So if you want to fullscreen the whole...