Problem viewing messages in Yahoo Mail

Moderators,

It appears that the font (and possibly other characteristics) in email messages may have been recently changed.

Until a few days ago, I had no problem viewing posts delivered to my Yahoo Mail. I have been receiving messages at Yahoo since 2009 when I was diagnosed. Now the font appears to have been changed (possibly to Courier?) and I have to scroll left and right to read the entire message. Before the font was changed, I did not have to do this.

Is it possible to change the font (and whatever else was changed) back to the original? It's somewhat frustrating to have to scroll left and right to have to read even a short message.

Thank you in advance.