Comment # 4 on bug 1117958 from Fabian Vogt

(In reply to Wolfgang Bauer from comment #3)
> I submitted the update for Leap 15.0:
> https://build.opensuse.org/request/show/653598
> 
> Tumbleweed will soon get 18.12.0 anyway.
> 
> Regarding 42.3 I'm not sure yet.
> 
> Closing as fixed for now though, please reopen if you do think an update for
> 42.3 is necessary as well.
> Thanks.

I'll try it on 42.3 tomorrow, I've made a simple PoC here.
For some reason it opens a dolphin window if opening a mail as .mbox file,
which I have to investigate further...
In any case, the fix seems to be incomplete, so this needs some more fixing for
15 and TW as well...