Screenbar version 0.3 adds a feature to enable and disable sound while taking automated screenshots.
Update
Screenbar is now available for download on the Mac app Store
What is new in version 0.3
A user called btecu opened an issue on Github asking for a feature to disable the sound in Screenbar. I thought that sounded like a nice feature to have in the app.
This is what the setting looks like:
Play sound when taking screenshot
Upcoming features
In the next version the GUI will be reworked. As it is now it’s not looking very good. It has got a menu and a setting screen, but I think these will work better when merged together.