I often find myself wanting to run the same aggregation against different environments. To do that, I create the aggregation against one of the environments, then connect to the second one and change the target database in the aggregation editor (via the server/database/collection dropdowns).

Since the introduction of the 'Overwrite Specification' modal, changing the server, database or collection shows the 'Would you like to overwrite the current code with the template of selected operator' modal for ALL stages in the aggregation. This MASSIVELY interrupts the workflow and should be considered a bug.