APM: same VS for two applications, but apm treats them as different sessions

As a genral update: My test this morning did not show the inconsistent behavior my bigip did show yesterday. My bigip did send me domain-cookie which there no longer configured in the webgui and tmsh also did show only some parts from a previously configured multi domain experiment. This now seems to be solved by removing them by hand in tmsh. After that domain-cookie option is working as expected - it even sovled the problem with app2 not working within iframes.

I also tried out the new v12 feature 'Profile Scope' within the access profile. Setting it to 'virtual server' also got things working. But since the productive bigip is v11.4.0 domain cookies have to be used - I hope it works there a little less problematic as in my lab.