I did search across every file (using Brackets), so I found the .js and .php files where it’s used, but those classes were not found in any CSS file in my installation. Sorry, ‘looking’ was probably misleading. I meant I had searched thoroughly, using any one of a number of appropriate tools 🙂
I did find *some* of the attributes of the button, but not, for example, where the ‘Add friend’ button is getting its colour from, which is different to the ‘Send private message’ button for example. Some CSS has to be differentiating those two buttons, surely? And the colour in mine doesn’t appear anywhere in any CSS except for a class that isn’t applied to these buttons at all.
It appears in the plugins ‘Message privacy’ an ‘BP Profile Privacy’ and appears in the front-end (under ‘Settings’ so that the user sees a heading, but it’s inconsistent because not all of the settings options have a heading.
