Markdown Here is a free and open-source browser extension that converts Markdown text in website forms to properly-formatted rich text. This a good way to start using Markdown everywhere you type, whether you’re drafting email messages in Gmail or writing blog posts in WordPress. The marketing material positions Markdown Here as a solution for email, but the extension can be used with virtually any website that supports rich text, including Evernote. See the list of compatible websites and services for more information.
To use Markdown Here after installing it, start typing Markdown-formatted text in a form, like a new email message in Gmail. When you’re finished writing the message, right click in the form and select Markdown Toggle, as shown in the screenshot below. Markdown Here will convert your Markdown-formatted text to properly-formatted rich text.
One source of frustration is the inconsistency in rendered output. Since Markdown Here relies on the features provided by whatever rich text editor you happen to be working in, the rendered output varies from website to website. This probably goes without saying, but you should be careful to examine the output before sending your email message or saving your file.
Markdown Here provides support for the following Markdown elements (as tested in Gmail).
|Line Breaks||Yes||You can also press the Return key once to achieve the same result.|
|Fenced Code Blocks||Yes||Syntax highlighting is also supported.|
|Automatic URL Linking||Yes|
|Disabling Automatic URL Linking||Yes|