Markdown Syntax Broken in Atom.io

Question

Markdown sytax won't render in Atom.io.

Here are screenshots of other sytax highlighting that work perfectly (and Markdown's, which does not).

Python

JavaScript

However, Markdown syntax doesn't appear to be working at all?

What I've Tried

I'm currently on the most stable version of Atom.io:

benjamingross@myhost:~$ atom --version
Atom    : 1.12.7
Electron: 1.3.13
Chrome  : 52.0.2743.82
Node    : 6.5.0

1. I've tried both the language-markdown and language-gfm packages. I even uninstalled the language-gfm package.
2. I've uninstalled and reinstalled Atom.io
3. Found this post, this post
4. I have changed to each and every UI theme and Syntax theme that comes stock with Atom.io (where every other language continues to work, but .md files or .markdown files do not)

I look at other webpages like the ones below, and it seems like other people have quite attractive markdown syntax highlighting out of the box with Atom.

From the markdown-preview webpage

Any idea on how to get the same beautiful markdown syntax highlighting as above?

BTW, my markdown-preview works fine...

Update

Here are the results of my ~/.atom/config.cson

benjamingross@myhost:~$ cat ~/.atom/config.cson 
"*":
  "bracket-matcher":
    autocompleteBrackets: false
    autocompleteSmartQuotes: false
  core:
    openEmptyEditorOnStart: false
    telemetryConsent: "limited"
    themes: [
      "atom-dark-ui"
      "atom-dark-syntax"
    ]
  editor:
    fontFamily: "monaco"
    fontSize: 16
    invisibles: {}
    softWrap: true
    tabLength: 4
  "exception-reporting":
    userId: "8f9a4104-acbd-9a9c-c4fa-51fefd430c1d"
  "markdown-preview":
    useGitHubStyle: true
  metrics:
    userId: "5b177b4431829ba54f99ac607c1f52478649eff8"
  "one-dark-ui": {}
  "release-notes":
    viewedVersion: "0.95.0"
  "spell-check": {}
  "tree-view":
    hideIgnoredNames: true
  welcome:
    showOnStartup: false
".md.text":
  editor:
    tabLength: 4

Answer 1

Without knowing the specific issue and under the assumtion that re/uninstalling didn't help - one culprit could be a user configuration possibly under ~/.atom/ i.e the main config file ~/.atom/config.cson.

Those files usually survive a reinstall on *nix systems.

Try backing it up or moving it and re-starting the atom editor so it generates a new one.