Displaying elements other than fullscreen element (HTML5 fullscreen API)

Question

When I "fullscreen" an element (let's say a div), I can't get anything other elements to appear (while in fullscreen mode). Why is that happening? How can I accomplish this?

Related: Is there a way to overlay a <canvas> over a fullscreen HTML5 <video>?

Resonate

Potentially relevant browser spec addition: developer.chrome.com/blog/what-is-the-top-layer – Steelwork

Answer 1

It seems that browsers (Chrome 28, Firefox 23) set the z-index of fullscreened elements to 2147483647 (the largest 32-bit signed number). According to tests, setting the z-index of other elements to the same z-index will cause them to show, but the z-index of the fullscreened element can not be changed (it can, but the browser just ignores the value — even with !important).

Maybe the only reference I could find to this:

https://github.com/WebKit/webkit/blob/master/LayoutTests/fullscreen/full-screen-zIndex.html

Also, in Chrome dev tools:

So either set elements to the maximum z-index, or, the better solution would be to just create a container element, make it so that all elements you want to display are children of the container element, and fullscreen it.

Resonate

When I tried this, it only worked in Chrome, not Firefox or IE11, though the z-index of the fullscreened element was set in all three. – Consternation

same here, 3 years later. – Dourine

Here's the Firefox solution: #45798713 – Dourine

After Chrome's update to v.69 this solution (which was also implemented by myself) won't work anymore, so a better one that seems to work fine is the Firefox one provided by Dalibor. – Buttonhook

Answer 2

I think you can just wrap video inside div and put there also canvas and then just make div fullscreen, not just the video.

<div class="fullscreen">
    <video></video>
    <canvas></canvas>
</div>

Don't start fight with z-indexes, you'll always lose one day.

Vaporing