Typora has limited and experimental RTL support by setting CSS attributedirection to rtl on editor style, but doing so every time you boot it up is a huge pain. So I decided to make subthemes of built-in themes to be RTL by default.
These themes are based on Typora's Github and Night themes and do include the infamous Vazir Persian font.
Download this repository (or one of its releases) as a zip file, then extract contents inside of "Typora-Persian" into Typora themes folder.
To find out where themes are stored, follow this procedure:
Typora > File > Preferences > Open Theme Folder
After extracting/copying the theme to this folder, restart the application and from Themes menu, select Persian or PersianNight.