Yep and you other quotebimsebasse wrote:ac, you are one of legio. I filed a "improved theme handling" feature request on Cinnamon's developer hub long time ago but it was quickly closed. For some reason it's a complete blind spot among developers, not recognized as the major cause of confusion and frustration it is.
"Cinnamon themes" only changes Cinnamon, for windows you need to go to "Other Settings"
and change "GTK+ theme" and "Window theme"
Which tells me too much tweaking just to get a unified theme across destop & apps. Then complete confusion and breakage of Gtk vs. Gtk+ version 3.5 vs. 3.6 not implemented correctly or differently breaking themes. Icon issues.
Cinnamon is pretty damn good but could do better about those issues. The other issues are more about gnome like no feature rich and powerful CD/DVD burning apps unless you cross the border to kde land for them kind of things or use wine. Still holes in what is considered basic window applications with few linux equivalents or choices.
And still peeved about the battle still going on with no resolution of the apps remember windows size & position. "It's the DE that is responsible" no...no...no "It's the Application responsibility to take care of that". And coming back years latter and seeing it still hasn't change and nobody willing to budge for the sake of the users out there.
Otherwise looking great and loving Cinnamon and waiting for the "Hot & Buttered Buns" edition!