[gawa]

Yes, sure. Although if multiple files or folders are selected, it's probably easier to just press the Escape key once instead of searching for each selected objects in the folder to unselect them one by one. What I was looking for was a reproducible way to make this right click menu appear. The sequence Escape+ctrl+righclick is a way to do that, it always work, wherever the cursor is, and no matter if the folder has many files or not. No need to look actively for a couple of empty pixels anymore or to think "What do I have to unselect before I can right-click to get a different contextual menu?".