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[Tyriar]

Fixes #3297

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Typical master build on Azure Pipelines ~15 minutes:

After:

[jerch]

@Tyriar Wanna move away from azure CI? Tbh I found the gh-action based CI more reliable (from other projects), than azure in xtermjs. I kinda never get timeout errors on gh-actions, while azure seems to cause testing issue from high load sometimes.

[Tyriar]

I do, mainly because it's a little more integrated and easier to get to the failures. It's looking quite nice so far, will see how publish goes

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[jerch]

Would merging the browser tests into one container defintion help to speedup things?

I also wonder, if we should add back safari/webkit testing at some point, though I dont recall, why we removed it in the first place. We kinda have a blind spot there atm.

[Tyriar]

If agents all get provisioned then as much parallelization as possible would be the fastest. The integration tests for each browser takes several minutes.

I think for webkit there were issues when it was originally set up and never looked into after that.