Yes, Codemirror. What I know about Codemirror I mostly learned by reading other people's code so I suggest that. Specifically code of silverbullet: https://gi

Yes, Codemirror. What I know about Codemirror I mostly learned by reading other people's code so I suggest that. Specifically code of silverbullet: https://github.com/silverbulletmd/silverbullet/tree/main/web/cm_plugins https://github.com/silverbulletmd/silverbullet/tree/main/web... (and a few other directories there). It implements very advanced Markdown mode, lots of code to learn from.