Extend PS canvas without generative fill.

I would love to see the equivalent of a "Mute" button on the generative fill taskbar, for the many cases I need to extend the canvas without using generative fill (extending transparent backgrounds). I understand GF is a cool feature, but the current implementation is very much "In Your Face". 

In the meantime, how do I quickly deactivate gen fill (without deactivating the whole bar)?

Any ideas?