One of the greatest (revolutionary I can say) features in Blender is when you’re, say, moving an object (while holding down the left click button) and all of a sudden you decide that you don’t want that, so you right click to snap it back to its original location.
You have no idea how much this simple option helps. sometimes when I’m moving or resizing the waveforms (while I’m holding down the left click), I always press right click thinking that it would undo but then I realize it doesn’t work in Audacity and I have to press Ctrl + Z to undo it.
This may not be that much of a big deal for simple projects but for bigger projects it can be a little bit challenging.
Hopefully a similar feature like this will be implemented in the future.