① How can I remove the files in the window? ② When there are a large number of files, the mouse scrolling is very laggy.

① Hello, after dragging a file into the window, how can I make the file in the window disappear? I haven't found a way to remove the file.
② If there are many files in the window and I need to scroll up and down to view them, the up and down scrolling of the mouse wheel is very jerky.