Font Issues since the Source button disappeared

Prior to the removal of the Source button, I was able to edit my font selection. When you select the font Georgia from the drop-down list, then look at the code it pulls in not only Georgia but several others. Previously, I would edit out the other fonts, and all recipients would see the Georgia font. Now when I select Georgia, what users see varies from email type to email. For instance, Yahoo Mail gets a blocky plain font I don’t even recognize on mobile, desktop and iPad. Gmail is the only mail service that I’m sure sees Georgia, but only about half of our email list goes to customers using Gmail. I tried coding the text in  HTML, and it worked beautifully, except it clipped. What do I do now to get the recipients to see Georgia and not some random ugly font and not get clipped?  Thank you.