AADL: Right button+ CTRL disables the popup
The normal behaviour is that if you draw a box with the right button pressed, at the time when you release the button it opens a pop-up menu to select what you want to add to the diagram (function, function type, etc.) Ok ?
However if instead you press Ctrl + left-click and you draw the box, it disables the feature. After that you can't do it at all
It somehow enters a mode in which this is not possible anymore. And it exits this mode only after clicking an option in the menu on the left to manually add an item to the scene. After that, it works back.