VS code. It has previews and works pretty well out of the box.

vim

Vscode, obsidian, Marktext.

Vim, with grip for previewing in a web browser.

Plain Neovim

haven’t seen anyone recommend Joplin Notes yet

• License: AGPL-3.0+
• Plugin repo
• Compatiblity: Linux, Android, Windows, and maybe Mac?

VS Code on my laptop, neovim when sshing to my servers, and Nextcloud Notes on my phone

Neovim with markdown preview plugin

Neovim or vscodium

GVim.

Check out https://ghostwriter.kde.org/ if you are looking for a GUI app with live preview, full screen mode, etc.

Vim with a plugin that lets me add a table of contents

Gedit & vs

Depends on the file, very simple files may only warrant npp, but VSCode for more complex stuff where live preview may come in handy.

Vim with vim-pandoc plugin

I don’t have any need to edit markdown, but I sometimes use Marker: “Simple yet robust Markdown editor made with GTK” as a viewer.