Hi @whyI, sorry to bother you again.
Your font CSS snippet worked perfectly.
Now, I have come up with a new way to annoy you. I want to change the font and the font size of the preview, the normal text, not the headings.
I have tried and failed with:
.markdown-preview-view p {
font-family: "font-name";
font-size: 20;
}
and
p {
font-family: "font-name";
font-size: 20;
}