Does anything change after you click the “ Detect Window Properties” button? I noticed that the “Window Types” options reappeared after I just did that on my Firefox window. (sorry - ignore that - it was the “Add property to the rule” window that popped up, not the list of Window types)
Regarding the “Window class (application)”, “Window types” & “Window title” drop-down lists, I couldn’t get the text to appear, but clicking on different blank lines did change the selection displayed.
When I “detect window properties”, the textbox is filled correctly, but the dropdowns stay blank. I think the problem is “simply” the display of the menu options, the underlying values are still there.