My many-years-old Apple magic trackpad died a couple weeks ago. Discovered the v2 version now works with Linux, and that arrived last week. And then...

I discovered https://github.com/bulletmark/libinput-gestures

Which has allowed me to do custom mapping of 3-finger gestures and, more interestingly, 4-finger hold.

I now have a "one touch" mute button for my machine. :)