I changed my AFK timer to 60 minutes, 30s polls and I’m having a lot of success with that. I might propose changes to the docs.acitivitywatch.net but I don’t want to suggest something that will need to be removed in a couple months. I’m too new to programming to be helpful with the code part, but I can help with documentation.
I’m having a similar problem and think that your solution would work nicely. Could you share how you changed the AFK timer?