If an application trigger is replaced with a new application trigger, but they both commit an application with the exact same name, will the new trigger carry on where the old one left off or create a new application with the same name but a new ID?
Once an application container is created with a name in a trigger that name becomes the “discovery_id” of the container. While you can change the display name of the application container its discovery_id remains unchanged.
Any future triggers that commit to the same application container name in a trigger will go to the same container based on the discovery_id.
One way to think about this is understanding that an ExtraHop Application is essentially just a metric container. Thus, you can have multiple Triggers all writing metrics to the same Application, simply by referencing the same unique Application container name, as @iodine mentions. Once the metrics are written, there is no tie back to the Trigger(s) which wrote the metrics or created the Application.
In short, yes, the new Trigger will write metrics to the Application container just as the previous Trigger did.