Candidate Module Custom Button, Web Tab Not using configured URL

Candidate Module Custom Button, Web Tab Not using configured URL

I have setup a Web Tab for testing going to https://www.bing.com I have then gone in a configured a button on the candidate detail page. In the configuration for the button, i added "?q=${Candidates.Country}" to the URL.

If i then exercise the button/link from the candidate detail page it does take me to bing.com. However, the configured query string is not populated. I have tired this with several other URLs, some application specific, and none of them get any of the query string parameters configured for the button. All the documentation indicates this is the way it should work, am i missing something, or is something broken?