A number of bugs we 've been bitten by in our installation have been fixed upstream. 5.0.13 is currently released in the FTP repo. Scheduling an upgrade for Oct 11 2016. 09:00 UTC . It should incur a small downtime of a few minutes.
So, I re-ran the migration scripts because of
If you upgrade from OTRS 5 Patch Level 2 or earlier, please run scripts/DBUpdate-to-5.pl once during the upgrade to fix possible issues with dysfunctional notification tags.
cause my memory failed me and could not remember if we had ran it before. Turns out it is not idempotent, so we should skip running in any later patch levels.
Those are not touched by the upgrade script as it seems. They have timestamps back in February 2016 (since we did the upgrade) so I assume that if anyone did not like them, they would have complained by now.
Looks good. Looking at the histories of the most recent tickets, only one notification is sent per agent (as it should be), and the duplicates are also gone from the user settings panel. At least in my case, I can also say that my previous notification settings were unaffected, both according to my user settings and de facto. While the duplicate was in place, I started to get queue update notifications; but when I just tested this by moving a ticket from Junk to info-de and back, I no longer got such a notification. In other words, the previous behavior was fully restored.