Show Activities Overview on button DOWN event
Coming from macOS, there is a perceived lag when using the Activities Overview (aka Mission Control in macOS). I was trying to figure out why that is, and it looks like this not a performance issue but a matter of which event to respond to.
In macOS, Mission Control is shown on mouse button down event. So you see all the windows as soon as you hit the F3 key. In Ubuntu 19.04, the Activities Overview is only shown when you release the Super key.
Also, if you press and hold the F3 key in macOS it will go to Mission Control, but will leave it as soon as you release the key. If you simply hit the F3 key, it will stay in Mission Control until the key is hit next time.
I guess, adopting macOS behavior is difficult because one might want to use a Super+AnyKey combination and go into Activities Overview instead, as soon as they hit Super. Maybe some other key can be used exclusively for Activities Overview?
macOS also supports third-party mice with 5+ buttons well out of the box, and one can map any of the extra mouse buttons to Mission Control in the Settings app. That feature would also be handy to have in Gnome. The behaviour is the same, the MC is shown on mouse button down event.