Implement copy-screenshot-to-clipboard on Web

[emilk]

Related

• Closes Space-view screenshotting on Web #8264

[github-actions]

Web viewer built successfully. If applicable, you should also test it:

• I have tested the web viewer

Result	Commit	Link	Manifest
✅	5d5350c	https://rerun.io/viewer/pr/8607	+nightly +main

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[abey79]

Seems that this PR broke meshes in Safari/GL. At least that's what I'm seeing with the web build, which I dont see in other PR.

edit: nvm, it's #8577

edit2: nvm, it's some more downcast typos

[abey79]

This doesn't seem to work on Safari:

[abey79]

code lgtm, but as noted doesn't work on safari

[emilk]

I am guessing safari isn't working because there is a frame-delay between the click and the screenshot being captured, and safari doesn't allow copying unless it in a direct response to a user action…

Maybe I'll just remove the button on safari.

[abey79]

We've had the same problem back then for copying text and eventually solved it. Any chance we can use the same strategy?

[emilk]

The solution was to run egui on-click, which works if the copy-action then happens on click.

In this case, the click results in a deferred screenshot capture that appears next frame, and so Safari says "whoa there, why are you trying to access the clipboard when there was no user action to trigger it?"