Moving to micro-task for stuff

[stefanpenner]

If we move to a micro-queue for more things, we may have some issues with window.open in some scenarios:

test page: http://static.iamstef.net/security-open.html

This may or may not be a blocker, but figured I would drop findings so far here. So we can decide.

What is this? Turns out, there are some security features that prevent window.open from causing a window to open in several cases. specific if it seems to be not legimately the result of a user interaction either nothing happens, or a popup blocker UI is provided.

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Now, the heuristics for "legit" vs "illegitimate" window.open attempt is abit fuzzy.

Table depicting:

	sync	micro task	raf	setTimeout
Chrome 55	✓	✓	blocker	✓
Safari 9.1.2	✓	nothing	nothing	✓
Safari 10	?	?	?	?
FF 50	✓	blocker	blocker	✓
IE Edge	?	?	?	?
IE 11	?	?	?	?
IE 10	?	?	?	?
IE 9	?	?	?	?

---

? needs to be tested

[chadhietala]

	sync	microtask	raf	setTimeout
Safari 10	✓	✓	nothing	✓
IE 9	✓	nothing	nothing	blocker

[rwjblue]

FWIW, #306 is starting down the path for microtask queues for autoruns and transitioning from queue to queue via microtask.

[dtapuska]

You should retest this on Chrome 72, rAF now works correctly due to redesign of user activation

[xg-wang]

	sync	micro task	raf	setTimeout
Chrome 90	✓	✓	✓	✓
Safari 14	✓	✓	blocker	✓
iOS 13 iPad	✓	✓	nothing	✓
FF 89	✓	✓	blocker	✓
Edge 80	✓	✓	✓	✓
Edge 18	✓	✓	nothing	✓
IE 11	✓	nothing	nothing	✓