We need certain "When sensor state is Up for at least ... seconds, perform" instead of ambiguous "When sensor leaves Down state after a notification was triggered, perform" (where a state can be Unknown, Unusual, etc.) in the same State Trigger with the 1st line "When sensor state is Down" from Notification Triggers. There is no option in Notification Triggers now and for many years for many users, according to kb.paessler.com.
Is there any way around?
P.S. There is no such a problem in other monitoring programs like Orion, WhatsUp, etc.