Hi @chrisonline
Welcome to Enpass family.
I would like to share that, in order to use Enpass Browser extension, the main app must be kept running in the background. The reason is that being an offline password manager, Enpass saves all your database locally on your device, not on any server. Whenever you visit a login page and click Enpass browser extension for auto-filling, then the extension securely connects with an Enpass app to fetch and auto-fill the details. For more details please have a look at our user manual link.
In this case, there is an option in Enpass settings to keep it running in the background by minimizing it to system tray. Also, you can set Enpass to autorun on system startup so that you don't have to manually start it every time the system starts.
Hope this helps!