Anyone not seeing "Apple ID Verification Code" dialog box to enter two-factor code sent to your trusted device to activate Mac OS X iMessage app?

Dooooh...well after reading Apple's article (Two-step verification for Apple ID - Apple Support) on how two-factor authentication works...I discovered that for those applications that do not support entering verification codes you can generate an app-specific password by signing in to your Apple ID account page and in the Security section, click Edit > Generate Password. So assuming the Mac OS X Yosemite iMessage app does not support verification codes which seems odd, I generated an app-specific password and entered it into the Mac OS X Yosemite iMessage Apple ID login dialog box and It worked.