Messages - bold font can't be changed to regular
Hello,
I've purchased a new macbook pro 13" with Yosemite system a week ago,
and for some reason, all messages that appear in the Messages app window are written in bold Arial font.
I can't change it to regular.
When I right click in the below form (where one can type a message), font type and size are changeable while actually typing, but only in that very "form", meaning it's not applied to the above messages that are sent. I don't know if I made myself clear enough...
May anyone help please?
Many thanks in advance!
All the best,
Loan
MacBook Pro with Retina display, OS X Yosemite (10.10.1)