In the « Snippet » tool, 2 cut modes are available :
•Removing mode (you select the part to delete).
To do so, use the "opened scissors" icon 
which is used to cut what you have selected between the blue and the yellow lines.
•Adding mode (you select the part to keep).
To do so, use the "closed scissors" icon 
which is used to keep what you have selected between the blue and the yellow lines.
