Add support for non-HTTP(S) bookmarks

[ghost]

Would it be possible to add support for non-HTTP(S) bookmarks, e.g. Steam. At the moment they can be added to the database just fine but when displaying them back the : (colon) is stripped out of the URL link so they break.

The bookmark appears to be fine in the database as per below screenshots:

But when viewing the page the : (colon) has been removed from the link

[deryaba]

The same thing happens with chrome:// links. Is there a possibility to allow any types of links?
There's many schemas like these:

• chrome:// (it's the issue what I facing with)
• magnet:// (torrent)
• rtsp:// (video cams)
• git://
• ftp:// (almost dead, but maybe still used)
• about: (I dunno if it's really used nowadays, just remembered about it)

So, here's a list of common schemas. It would be nice if you add at least the most commonly used ones =)