Log Alerting - Clear condition based on rolling window

I had a use case recently where a customer wanted to alert based off of a log message, and then keep the alert active until the log message is not seen for X amount of hours.

Currently we can alert off of a log condition and keep the alert active for X amount of hours, but there is no rolling timer to check if the log is still occurring. So once the static alert-clear window ends, the alert clears and a new one triggers the next time the log comes in.

It would be really useful if we could have an alert clear window with a rolling timer so that the alert clears if the log is not seen on the alerting device for X amount of time.