First proposal of dom layers

[cabanier]

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Preview | Diff

[cabanier]

@AdaRoseCannon here's the long promised PR for layers :-)

[AdaRoseCannon]

Thank you so much ⭐

[msub2]

Any interest in picking this back up? DOM layers would be very useful to help fulfill usecases similar to what https://hyperbeam.com/ provides, but in a spatial context.

[cabanier]

There is interest but every time we discuss the proposal, we come up with more security problems that require workarounds. :-(