The protocol (for example, http:// or https://) that should be used for navigation to the Webroutine specified in the on_click_wrname property.
Typically you might use this property when it is necessary to switch to or from secure-mode processing. Otherwise it is not usually necessary to specify this property.
Blank. This is equivalent to the current protocol being used.
A valid protocol, in single quotes. If specified, it is usually 'http:' or 'https:'.