Comment # 3 on bug 1212798 from Dominique Leuenberger

(In reply to Franck Bui from comment #2)
> (In reply to Dominique Leuenberger from comment #1)
> > That sounds like https://bugzilla.opensuse.org/show_bug.cgi?id=1041742 still
> > being present.
> 
> I'm not sure.
> 
> This bug is about %transfiletriggerin not being executed *if* the package
> being installed has a %posttrans script.
> 
> Otherwise the %transfiletriggerin script is executed. Currently it's
> executed at the end of each package installation instead of the end of the
> transaction due to the design of the current backend transaction.

which is exactly what the bug was about - see
https://bugzilla.opensuse.org/show_bug.cgi?id=1041742#c2