I haven't read about a

badlop — Wed, 07 Feb 2018 11:35:00 +0000

I haven't read about a similar problem before. Maybe you have some custom module installed?

Try to join a room only you, does the problem appear? Maybe it's a specific room occupant client the one that sends such duplicated messages?

You can set loglevel to 5 in ejabberd configuration file, but that would generate a lot of logg lines in a production server...

For loggin TCP traffic, you can disable encryption in 5222 port, and tell your users that temporarily the traffic will be unencrypted.

Oh, forgot to mention, we're

gushi — Wed, 07 Feb 2018 05:20:12 +0000

Oh, forgot to mention, we're running ejabberd-17.11 from FreeBSD 11.1 packages.