I figured out you can use an HTML <img>
like so:
- Windows:
<img src="app://local/C://Users/username/Documents/obsidian_notebook/state_transition.png">
- Linux (you have to have two “/” before “home”):
<img src="app://local//home/username/Documents/obsidian_notebook/test.jpg">
- Mac (it doesn’t matter if you have one or two “/” before “Users”):
<img src="app://local/Users/cusername/Documents/obsidian_notebook/test.jpg">