Thank you for your reply.
The use of the word "buttons" can be confusing.
I should have been more clear. In this case, I'm addressing when the field
Type is
Radio Buttons and it has its
Display set to
Radios, not buttons. For example, the
Gender or [b Age Group[/b] fields on this site when editing my profile (
www.joomlapolis.com/profile-edit
About Me tab).
In the attached screenshot, the radios for Gender have the CSS class of .form-check-input because they are not required. Even if they were required, they should also have that class so they display properly.