Is Timer disabled in Live Activity / Widget?

In a Live Activity, we have use case to show some countdown for the user o finish some tasks before a deadline. When the deadline reaches, we want to show a different message. We create a timer in our Live Activity codes, listen to it and want to change the text when the timer fires. But, the timer never fires. We write another simple codes to verify:

We didn’t see the countdown effect. We are wondering if

  1. Timer is disabled in Live Activity, so it never fires

or

  1. State variable is disabled, so even Timer fires and changes State variable’s value, View cannot pick up the new State variable’s value

You can't use timers in a widget, so I'd guess they're also disabled in Live Activities, too.

You need to implement a timeline for the events, i.e. add an entry for the start time, and one for the end time, and hope it works. One of my apps has countdowns in the widgets, and everything would be far simpler if I could use timers, but I can't.

Is Timer disabled in Live Activity / Widget?
 
 
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