The PyGTK3 application sits in the tray, waiting for you to type, and as soon as you start typing it mutes your microphone. The Hushboard microphone icon displayed as a tray/appindicator changes depending on your microphone state: enabled or muted. The tray also allows you to pause Hushboard and quit the application.
I'm going to try this out as my mechanical keyboard is especially loud when typing. It's working fine on Manjaro Linux for me and I see there is a Snap install too.
See Hushboard Mutes Your Microphone While Typing
Hushboard is a new Linux program to automatically mute the microphone while typing (and unmute it when typing stops).