Default Font for Pasted Text.

This is perhaps a silly post for someone who has been using Pegasus for so long but it is a niggle I come across every time I paste text into an email.  The Font used is always the rather unpleasant Time New Roman and I always use Arial which is a much cleaner font.  I have never found a setting for this in Pegasus, is there one or will I need to change something in Windows 10?

Thanks for reading this

Chris