Non-standard protocol links with numbers aren't rendered as links

The new editor does not properly create links that do not use one of the standard web protocols when inserting with the Insert Link dialog (e.g. http://, ftp://). It creates the <a> but without a href attribute. In 3.5 and earlier, you could create a link for any protocol type using wiki markup: [something://mysite.com]. Inserting the wiki markup results in the link being stripped and the URI appearing as plaintext.

The only workaround is to insert a link manually with the HTML macro, but not all sites will be able to enable this macro for security reasons.

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The fix in 4.3.7 allows non-standard protocols, but not if they have numbers in the protocol.

e.g. exp://Ticket/12345 works fine but exp2://Ticket/12345 is not rendered as a link.