Yahoo eMail Font Size Becomes Very Large


New Email
Printing an email has been working fine for years but lately the font size prints about 3 sizes larger than it normally had. I'm having a similar problem in libreWrite except the characters on the screen are becoming large yet the application says their size is still the same. I'm not looking for an answer to the libreWrite proble; I just threw it in as it MAY lend context to my email question.

Thank you

Win10 Home 64-bit, Intel Core i7 6700HQ @ 2.60GHz, 16 GB, FF 47.0.1