Start Dolphin File manager.

First time a file item with right mouse button is selected.
On the menu which shows up "cut" or "copy" is activated. 

The mouse is moved off the file item. Left mouse button is
pressed to deselect file item. 

Right mouse button is pressed again not on any file item. 
The menu showed up does not contain a menu entry "Insert Item" 
as expected.

Now a second time the same file item with right mouse button
is selected. On the menu which shows up "cut" or "copy" is 
activated again.

The mouse is moved off the file item. Left mouse button is
pressed to deselect file item. 

Right mouse button is pressed again not on any file item. 
The menu shows up does now contain a menu entry "Insert Item" 
as expected.

That is "cut","copy" and "paste" only work when activated 
two times, means every second try.

This behaviour can be reproduced.