@rob.bennett can you try opening the workflow which needs to be debug and then click on debug file directly instead of debug (don’t click on drop down)
Issue 1: Debug the current workflow only
Open only the current workflow file which you want to debug and Click Debug File or use F6 to debug the current file. Screenshot attached below
Issue 2: Browser Close. Once verify below settings as well
Project Settings:
a. In the Project panel, go to Project Settings.
b. Navigate to Activities Settings > UI Automation Modern.
c. Modify the Application/Browser – Close [Run Value or Debug Value] based of requirement [Screenshot attached below].
d. Click OK to save changes.