Custom buttons fail to open non https/https links like tel://, sms://, sip:// and sips://

Custom buttons fail to open non https/https links like tel://, sms://, sip:// and sips://

Hello,

I'm currently trying to add functionality that would require the use of certain URIs.  For the immediate moment I'm needing to use those that are listed in the title of this post (with or without the "//"),  but I'd like to future-proof my request and say that it would really be stellar if this could work with *any* URI.

Unfortunately when I attempt create a message card with open.Url assigned to one of the custom buttons in the message card it just errors out.

In addition I've also attempted assigning a function to the button instead and executing openUrl within the function. In doing so I've tried  using "same window", "new window", and "parent window", but to no avail.  While there are no errors being generated in the log, it doesn't do anything either.

Is there a way that this can be made to work correctly?  After all, open a URI from the shell shouldn't be any different than a URL, no?

Thanks,
Bryan