marijnh/CodeMirror — pull request #1892 by brandonwamboldt (2013-10-19 17:08:07+00:00)
Title: [gfm] Adding support for ~~strikethrough~~ text

Fixes #1887.

> GFM adds syntax to strikethrough text, which is missing from standard Markdown.
>
> ```
> ~~Mistaken text.~~
> ```
> becomes
>
> ~~Mistaken text.~~

Added test cases, added a new style (strikethrough text is displayed with a strikethrough to be consistent with how the rest of the markdown is rendered).