Is there any text editor which supports Markdown (Ask Ubuntu's formatting style)?

Try Retext which supports markdown. Retext has been in Ubuntu since 12.04 precise. For earlier Ubuntu releases, or if you want a more recent version of Retext, get it from the project home page or from a PPA.

sudo add-apt-repository ppa:mitya57/ppa
sudo apt-get update
sudo apt-get install retext

This will install Retext.

If you want a gedit plugin with markdown support:

  1. Download this and extract the file in ~/Download directory.

  2. Open a terminal, cd to the ~/Downloads/gedit-markdown-master directory and run ./gedit-markdown.sh install.

  3. Restart Gedit and you have a markdown plugin, enable it and enjoy ! .

Note: You can anytime preview markdown by entering Ctrl+Alt+M.


You can try Retext or Haroopad (both let you edit your markdown code and preview it)

Retext

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Image source

Haroopad

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Image Source - Haroopad


Remarkable

Remarkable Main Screenshot

Remarkable is a fully featured markdown editor with the following features:

  • Live Preview
  • Syntax Highlighting
  • Support for GitHub flavored Markdown
  • Editor specialized exclusively for Markdown
  • Custom CSS
  • Export to HTML & PDF
  • And More...

Remarkable with Dark GTK3 Theme

Homepage: Remarkable App
Source Repo: Remarkable on GitHub
License: Open Source under MIT License
Download: Remarkable's Download page provides deb package for Ubuntu