Is there delegation involved, i.e. User2 has addresses of User1 defined in his identities or the folder is just shared?

Confirmed. And this looks like a different issue.

From RFC5230: "UTF-8 characters can be used in the string argument; implementations MUST convert the string to [RFC2047] encoded words if and only if non-ASCII characters are present."

Please, be aware of the fact that there can be three different capability response formats

- when connecting..
S: * OK [CAPABILITY IMAP4rev1 ...] Server ready.

Is this related to T1139 ?

That chunk of the config wasn't the culprit here. It's there to make sure resource names are unique - by automatically generating an unique name if already entered name exists.

Call self._bind() before using self.entry_dn() method. @FIXME: _bind() should
probably be called explicitely by entry_dn()

Get rid of unbind() and close ldap_priv connection on disconnect()

Ok, I forgot about this setting. It looks like upper-case Y is not supported. Here you have the list of supported formats: https://git.kolab.org/diffusion/RPK/browse/master/plugins/calendar/config.inc.php.dist;e8aa73aae3e45791206b2912c083ff48bd2a244a$39

Links are fine, but the images are broken. E.g.

How did you set this date format? From what I see for year only one "Y" letter should be used and this works. If I set date_format = 'd.m.YYYY' replacement works, though not in a way you'd expect.

Cherry-picked in 194690f59b

Did you try in different browser? Exactly from where did you get these plugins?

Hmm... I'd expect clean() in this line https://git.kolab.org/diffusion/S/browse/master/lib/kolab_sync_data_email.php;a6b7464233dcf471293103aa735d42ea8f3c7870$350 would fix such issues. Could you compare this with what you have installed?

Kolab-syncroton package version would be more relevant here. Sounds like a it could have been fixed in https://issues.kolab.org/show_bug.cgi?id=3844.

This is 3% discount for yearly payments. No bug for me.

Can we have some more information on this, e.g. precise steps to reproduce or if wallace is involved, etc.

I don't know why this ticket exists, but there's T1278 which was for Roundcube. So, maybe this is to check on kdepim.

Likely involved code here: https://git.kolab.org/diffusion/RPK/browse/master/plugins/libkolab/lib/kolab_date_recurrence.php;81cd96ad4b0bf2ed8e0bd26d58b566165fa1f58e$136 And one more: https://git.kolab.org/diffusion/RPK/browse/master/plugins/libkolab/lib/kolab_storage_cache_event.php;81cd96ad4b0bf2ed8e0bd26d58b566165fa1f58e$43

Looks like a feature/bug of PHP where numeric array keys (here folder names) in foreach are converted to int. I'm talking about the loop in kolab_sync_backend::folders_list(). I'm working on a fix.

Roundcube displays free-busy for max. 16 weeks into the future. So, you will not see free-busy information when you create an event more than 4 months from now. That's probably not a big issue, and maybe simple config option in Free-Busy would be enough for a solution.