I tried several variants but not even this does work :
Any pointer welcome
OK! It was my fault!
Forgot about the purge-Flag. Edited it above.
But it still does not work.
Sorry for my confused postings!
Plone 5 is a bit creepy. Sometimes it works perfectly, sometimes it works a bit, sometimes it does something. Please accept the confusion of my posts as a reflection on my state of mind working with Plone 5:
I If you're seein' things runnin' through your head
Who can you call?
At first I thought it were browser caching problems - and I am sure there are still some - but even as I minimize the browser impact Plone 5 remains creepy.