Can't move threads

[Mark.B]

No, you'd need to restore a backup from before you upgraded.
We don't recommend the use of alpha and beta versions on live production sites as development is not complete.

[geeklingo]

Can I simply downgrade to 5.1.0?

[Mark.B]

Can you please try using 5.1.0 instead?
5.1.1 is still in alpha and may have issues.

[geeklingo]

Just upgraded from 4.2.2 to 5.1.1a9 and can't move threads as a moderator. I get the following error message:
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