After migrating my app to 15.1.8, i've found the app title was not there when activating any view.
Also i've found it is related somehow to using skins; if you put the "standard windows theme" the bug is not visible.
Also, the problem is with the "old templates"; i've modified the MainDemo to reproduce the problem.
A hotfix for that would be very welcome.
Cheers!
I have reproduced this issue in the Main Demo. Our developers will work on it.