Re: pgsql: Restore replication protocol's duplicate command tags

On 2020-Oct-14, Alvaro Herrera wrote:

> Add a test case that shows the failure.  It might still succeed even
> without the patch when run on a fast enough server, but it suffices to
> show the bug in enough cases that it would be noticed in buildfarm.

Hm, this failed on sidewinder.  I think the "wait for catchup" stuff in
logical replication is broken; I added a wait for sync workers to go
away after the normal wait_for_catchup, but evidently it is not
sufficient even with that.