I track how long spells or conditions last by just scribbling down the condition and a duration on my initiative sheet.
For example if the Barbarian rages I’ll just write “Rage - 10” and each round I add a tally, when we hit 10 it’s over. So there’s no “extra” tracking, if someone delays their turn I just add a tally mark.
It might be a bit harder on digital tabletops if you have to go in and edit things.
Adding a new form of long-term madness to my tables…”you are convinced you’re part of a simulation”