MD links should automatically add scheme

[caseywatts]

Links without an http:// prefix aren't read correctly in Apple Mail. It tries to use the x-msg protocol to open them instead of a web browser, which doesn't work.

I believe GMail normally corrects for this by prepending links with http:// but markdown-here avoids that fix.

See also:
http://stackoverflow.com/questions/11033342/php-mail-function-prepends-x-msg-to-all-links

[adam-p]

I think I see what you mean. I'll detail some reproduction scenarios...

In Gmail, without using Markdown Here, http:// will automatically be prepended in these cases:

• You include some plain text that looks like a link without the scheme; like: www.example.com/index.html.
  • Prepending happens at send time. It does not appear in the text/plain alternative.
• You create a formatted link but don't specify the scheme.
  • Prepending happens when the link is formatted. It does appear in the text/plain alternative.

In Gmail-with-MDH:

• If you include some plain text that looks like a link without the scheme -- like www.example.com/index.html -- it won't get picked up for MD auto-linking and Gmail will take over and prepend http://.
• If you specify a MD link without the scheme -- like [Example](www.example.com/index.html) -- http:// will not get automatically prepended.

Recipient client behaviour for schema-less link:

• Apple Mail: The x-msg thing.
• Gmail and Outlook.com: No problem. Quietly prepends http when opening the link.
• Yahoo: Looks like a link, but you can't click it. There's not even a hover-hand-cursor.
• Thunderbird: Clicking the link doesn't do anything.

I'm going to change the title of this bug.

[adam-p]

Fixed in rev a6ce210

[adam-p]

For future reference (I'm pretending I'll see this again):

This feature/fix makes a lot of sense for in an email environment, where relative links make no sense, and where the writer doesn't control the scheme at the time the reader views the rendered result.

However, it does not make sense for more web-page-like uses (like blog posts), where the writer might want/expect relative links or to leave the scheme blank so that it matches the scheme that the reader is using to view the site.