Skin cannot be opened in painter if Icon.dds is missing

[TMarc]

If a skin has no Icon.dds file, trying to open it in the Painter results only in some delay, a sound, and then nothing, ManiaPlanet stays at the car skin selection screen.
Weird thing: the skin actually appears correctly on the car booth...


Besides that (second issue), any DDS file present in that folder is considered as skin, but it can't be loaded either.
Here I had taken my own Icon.dds out of my skin and placed it aside the actual skin.zip file:


Of course the icon.dds does not match the model, but the game should simply ignore "skins" that have the size of an icon (128x128)

Original finding by Sparkster.