Onion hosts are not recognized as URLs and thus get funny treatment.

As the linked post demonstrates, if you enter a link like this:

[mail2tor](mail2torjgmxgexntbrmhvgluavhj7ouul5yar6ylbvjkxwqf6ixkwyd.onion)

mbin thinks it’s something else. Indeed it’s not a URL due to the lacking ‘scheme://’, but it’s bizarre what it does with the links.

Since SSL is not generally needed for onions, every link would require some effort to know whether it should have a scheme of http:// or https://. Mbin should just pick one of those schemes arbitrarily.. certainly not whatever it’s doing at the moment.