The duration attribute is showing the time the timer is set to
The remaining attribute is showing the time remaining, but ONLY updates if the timer is paused.
What we need:
An attribute remaining_realtime that is continues updated to how long it is to timer ends.
alternatively a netter way to show this in the dashboard, it is just the entities-card that is showing countdown-time if timer entity is added. All other card is showing just “active”, “idle” ect.
is due to the states are saved in the recorder history and keeping it free from clutter was the reason.
However with some other entities being omitted or throttled down a few months ago (sun is the only one I can remember now, perhaps that is the only) then maybe the same logic could be applied to timer entities?
But then again each state update will cause events, so perhaps that is also a reason to not have it counting down in the state.
I believe, someone who uses a lot of timers might notice a change where it keeps updating states all the time. But that is a guess.
You could template your own countdown using the duration and remaining.
In my example I can use {{ relative_time(states.switch.zwave_6_switch.last_changed) }}', but it looks like it just updates when i refresh lovelace. Tested in template-card and custom mushroom-chips-card