Lets say you want to open a new instance of "xfce4-terminal" while one is already running. REPRODUCE: Turn off "windows" under Plasma Search (Settings). Open the Plasma Overview, type "term". Expected Behavior: Overview offers search results according to the search settings -- the same behavior as if no instance was running yet. This is how it worked in the last version, I believe. Actual behavior: Overview offers the already running window and nothing else.
I think you are getting two things mixed up here. The Plasma search settings determine which categories show up as a *text* result for the search box that is present in the overview, application launcher, etc. It has no effect on filtering window thumbnails in the overview effect. In the overview effect, the search box additionally filters the windows shown, and text search results appear only when no open window matches. This behavior was introduced recently and is not configurable.
Oh, sorry, I did not realize those are now separate. That is unfortunate, it was my favorite way to manage windows. Any chance of adding the customizability back if I re-file this as a feature request? Thanks
Sure, go ahead.