append coverSlip to fullscreen element instead of body

[FlorianMaak]

Resolves #4259

This PR checks if there is a fullscreen element and appends dragelements coverSlip to this element instead of documents body.

[alexcjohnson]

Thanks @FlorianMaak! But it looks to me as though the unprefixed fullscreenElement is not yet available everywhere - perhaps only 45%? In some of our other packages we use fscreen to normalize this.

[etpinard]

Thanks very much for the PR @FlorianMaak - beyond browser support, it would be nice to write a test in the dragelement_test.js suite to lock down your fix. Would be interested in attempting to write a test?

[FlorianMaak]

Sure. Going to migrate to fscreen and add tests as soon, as I'm at office tomorrow.

[FlorianMaak]

Relating Tests: I think, we need to edit the karma config to work with fullscreen. Per default karma does not support fullscreen mode :/

karma-runner/karma#2292

[etpinard]

I think, we need to edit the karma config to work with fullscreen. Per default karma does not support fullscreen mode :/

Right, writing a "real" test for fullscreen might be difficult and quite frankly not necessary.

That said, if should be possible to test the new logic using jasmine spies.

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I'll be offline for the next two weeks, but @archmoj should be able to help you out if you run into problems.

[etpinard]

... and as for the failing tests. Merging master post #4321 should make them go green ✅ again. Sorry for the inconvenience

[archmoj]

@FlorianMaak could you please merge master into this branch and resolve the conflict?

[gvwilson]

This pull request has been sitting for a while, so I would like to close it as part of our effort to tidy up our public repositories. I've assigned it to myself to keep track of it; I'll wait until 2024-06-17 for someone to say it's still relevant and they'll to take it on, and otherwise I will close it then. Thanks - @gvwilson