Buttons can have a flag set with UI_BUT_ACTIVE_DEFAULT to indicate they are the default button among a group. The button executed if just pressing "Enter". For example the "Save" button on the "Do want to save?" dialog.
Unfortunately the way that indication is currently drawn has a few problems.
- The color is based on the "Inner Selected" of "Menu Item", which is not intuitive to find.
- The color will usually look muddy since it is 50% mix of that color and the regular color.
- The bend radius of the corners is hard-coded. So if you change the roundness of the buttons the corners will not match. For example you can see this if you make the buttons more or less rounded:
This patch fixes these problems and leaves the button looking nicer. The following shows current look on top, what below shows after the patch is applied. If you look closely at the top one you can actually see that the corner radius differs between the buttons and the corners of the Save button looks a bit grey since the blue isn't quite covering up the gray at the corners.