Sleep timer with time slide control?

[fritz_hh (Fritz Hamburg)]

I would like a switch with a flexible slide control for the time that passes until several switches are turned off.

I have found the following example here:

Manual timer in frontend

Hey, I would like to add a timer to my frontend, but it should be startable via an input boolean. So, when I switch the input boolean to active, the timer starts and I see the remaining time. When I turn it off, it will stop. I will also send a notification to my phone when the timer ends (I already implemented notifications, should be no problem). My wife would like to have some timers, for example to see when the washing machine is done. Therefore, I am going to define multiple timers (for …

And the Timer discription " Control a timer manually":

Timer

That sounds very good, but I have trouble understanding it.
Do I need to watch out for something special with lovelace?

[DrSpaldo (Doctor Spalding)]

Did you ever figure this out?