编辑器

Editor.js (editorjs.io)
Summernote - Super Simple WYSIWYG editor

Markdown

JavaScript Markdown Editor - SimpleMDE
Editor.md - 开源在线 Markdown 编辑器 (pandao.github.io)
mdnice/markdown-nice: 支持主题设计的 Markdown 编辑器,让排版变 Nice (github.com)
hinesboy/mavonEditor: mavonEditor - A markdown editor based on Vue that supports a variety of personalized features (github.com)
benweet/stackedit: In-browser Markdown editor (github.com)

md-block: Render styleable Markdown in your HTML (verou.me)

https://github.com/0xGG/crossnote https://crossnote.app

桌面版

marktext/marktext: 📝A simple and elegant markdown editor, available for Linux, macOS and Windows. (github.com) 推荐

Zettlr/Zettlr: A Markdown Editor for the 21st century. (github.com) 可以用

notable/notable: The Markdown-based note-taking app that doesn’t suck. (github.com)