I moved a set of file to another partition by dragging
them to another tab, After the moving a file was
treated as a directory for no reason, It's file size
became 0 and appeared on the tree view.
Of course, the file was destoried.
I double click the "file" on the tree view, PCManFM
appeared a warning "It is not a directory" (or
something I can't remember) and crased.