ok, but we could just do this with code like before. thumbnail code is pretty simple: make a thumbnail sprite, have it go to the front layer and set ghost effect to 100 forever, but keep it shown. that way when the project stops it will appear. if u want a thumbnail from ur gameplay (or just whatever happens during the time the project is on) then screenshot it or copy and paste assets from the scene. there are even thumbnails that move and ones that activate movement after the project is stopped! what im saying is that the set thumbnail option might be easier, but not necessary. no hate.
all me except i used the set thumbnail button to set the thumbnail XD