Meteor 3.0 support

[bhunjadi]

Is your feature request related to a problem? Please describe.
Support Meteor 3.0.

Describe the solution you'd like
Switch to *Async methods.

Describe alternatives you've considered
n/a

Additional context
I think we'd like to merge as much as possible from the open PRs and then start working on Meteor 3.0 support.

[github-actions]

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