Hot answers tagged computers
Ktimetracker Although I have no experience with this particular software, it might suit your needs. It's from KDE, so if you are using other Desktop Environment it might install a lot of dependencies. https://www.kde.org/applications/utilities/ktimetracker/
I use Hamster. It meets all your requirements. I have mine set to track to the nearest 1/10 of an hour (6 minutes). If there is inactivity for that period, it stops tracking but also every 6 minutes a 5-second tiny window pops up in the corner to remind you as to which project you're currently tracking against...to included you're currently not tracking ...
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