Typora — a markdown editor, markdown reader. — A nice Markdown editor, for multiple platforms. I use it for journaling, note taking and keeping references. It's not extendable, but flexible in use.

Editor.js — Seems to be a great editor, based on blocks.

codercom/code-server: Run VS Code on a remote server. — Found this when @frenck talked about the Hassio VSCode addon.