Why is https: optional?

http://www.w3.org/MarkUp/Forms/wiki/XForms_2.0#Submission_Options

"Other bindings, in particular to the URI scheme "mailto:" may, and the  
schemes "https:" and "file:" should, be supported."

I understand why mailto: and file: are optional, but not https:. Can  
anyone enlighten me?

Steven

Received on Thursday, 1 December 2011 16:09:07 UTC