I work as a secondary teacher. My students requested I put some kind of countdown clock on the screen, so they can better manage their time. I additionally need to display messages, at specific times of the day, so they know when it is time to clean up their work, etc. I'm using Xfce4.
I think this can be done using a bash script that consists of a while loop that constantly checks the time, and sends the messages and countdown status to a heads-up like transparent text appearing about all windows.
Is there any software, similar to GTKDialog, but rather than displaying pop-ups, instead shows a transparent heads-up display, above all open windows, and can receive updates from a bash script?