It confused me at first because I don't even currently have IrfanView installed... I see now that it is #61 in JLicons.dll, mystery solved...
Anyway, in my Folder Favorites, if I have "Live Folders" enabled then the top-most icon in the dynamic submenu has the wrong icon (Irfanview, rather than generic folder).
I just started seeing this today, even though I upgraded a day or two ago... So maybe it's my settings?? IDK. Note that it's not just the folder in the screenshot. It's any live folder with the generic Windows folder icon. Folders that explicitly have a custom icon assigned display as expected.
QAP 11.5.2.1.1 beta x64 on Win 10.