I've added ' toolbar="full" ' to my richtext element and that all worked; the toolbar now shows font controls and I can supposedly change the font and the font size.

However, when I actually highlight all text in the box and change its font/font size, it is completely random as to what the result is. I tried setting all my articles to have Arial with size 14, yet they all came out differently - the size was different across them all and the line spacing too. There was no consistency.
Sometimes changing the font/font size just didn't do anything at all, and I would have to change the text to a completely different font like comic sans and then back again just to make it do something.

How can I fix this?

Thank you