Does a timer-triggered Azure function execute if an instance of the function is already executing?

I have an Azure Function App with the [TimerTrigger(...)] attribute, which is scheduled to execute every morning.


Suppose you manually execute the function via the Function Menu Blade -> Code + Test -> Test/Run, as shown at the bottom of this message. What happens if this manual execution of the function is still running when the time specified in the TimerTrigger attribute arrives?



* Will the manual execution be interrupted by the timer-triggered execution?

* Will the manual execution prevent the timer from triggering a new execution of the function?

* Or will a new instance of the function be kicked off when the timer triggers it, running in parallel with the existing manual execution?