Yosemite Mail context menu not working

Since the installation of Yosemite, Mail context menus no longer work. Control-clicking on a hyperlink in a mail messages opens a context menu containing these items:

Selecting any of the first 3 has no effect. Just clicking on the hyperlink will switch to the browser (Safari) and open the link. Clicking on "Services" does display a list of Services, and "Open URL in Firefox" at least seems to work. However, "Open URLs in Safari Tabs" does not. This seems to indicate a possible disconnect between Mail and Safari in particular.

I've seen this problem in the Yosemite beta, the 10.0 release and the 10.1 release. I haven't heard of many encountering this problem, but I have heard of a few. Has anyone here seen this, and maybe found a resolution for the problem?

Operating Environment

MacBook Pro (Late 2011), Mac Pro (Late 2008)

Yosemite (OS X 10.10.1)

Mail (Version 8.1)

Safari (Version 8.0)