Thanks for your explanation. Just before your message, I could not understand why one kerbonaut have both "first..." ribbons for landing and EVA surface, and the other only one "non-first..." for EVA surface. I think some additional info in the tooltip will be the answer for my second second question. As for me, I understand that each "first ..." superseedes the "non-first" ribbon, but it hard to me when one "non-numerical" ribbon supresses the other with different name.