If custom config not empty on a site, different gear icon color

Is your feature request related to a problem? Please describe.
My colleagues and I manage quite a few virtual hosts. Because of this, there’s a human element involved: the UI isn’t clear enough in this situation, and sometimes we forget that certain sites have custom configurations. We start editing the config right in the standard npm GUI, even though the custom config overrides these settings on some sites.

Describe the solution you'd like
The "Settings" button in the upper-right corner of the "Edit Proxy Host" window could be a different color—say, orange—if the custom config for that site isn't empty. Otherwise, it could stay as is.
I think this would make the UI clearer, especially when used by a team.

Start by locating the frontend implementation of the Edit Proxy Host window, especially the Settings button and custom configuration field. Confirm how the field's empty and non-empty states are represented, then verify that the button's color changes only for sites with custom configuration and remains unchanged otherwise.