https://bugs.winehq.org/show_bug.cgi?id=56431
--- Comment #21 from Wagner.a18@yahoo.com --- So in the meantime i got the sourcecode and debugged the comctl32 and its file “treeview.c” myself.
I was able to narrow down the problem to the function call TREEVIEW_SendExpanded (line: 3396) within the method TREEVIEW_Collapse.
Before calling this method, the affected item has a child and after the call it has 0 children and therefore the module thinks that it does not have to draw the + sign.
Does anyone have an idea why TREEVIEW_SendExpanded() is called at this point? I think this is unnecessary, if I remove the line, then it also works.
I added Treeview_Collapse.log to have a look into my problem. I added TREEVIEW_Collapse.c with my added trace calls.