Timecard allows you to track how much time you spend on tasks. It offers a clean, responsive one-window interface that allows you to quickly configure your time tracking, and then hides away in the system tray until you need it again.
Features:
Does not work with Linux Mint 21.3 Cinnamon. Installs from the Linux Mint Software Manager with no errors, shows in the menu system, but does not work (there is a brief spinning mouse indication and then nothing).