wp-config configuration for staging boxes
In my case, I use a separated frontend client to connect to wordpress which acts as a headless cms. In those cases I can not test with staging boxes of my actual box because the wp-config needs to differ a little (for example CORS -> cant use the allowed frontend from the productive destination so I go with localhost for staging, therefore the wp config needs that as a parameter). Staging boxes always make a duplicate of the current box without the possibility to change its wp-config for testing purposes. I know my case is very specific, but I just managed to set this up properly with a second demo-box, which is a perfect replacement for that. For less database mess on your side I recommend making it possible to edit those files via a additional entry in the staging environment dashboard.