It got introduced in the first patch (I think).  Although it doesn't seem to apply to battles, and the side where the Start Menu is (if on auto-hide) doesn't scroll very easily.

There has been a bit of a miscommunication.  People who started from the second beta (first patch) and later need to download the "Full Beta" file from Stardock, then install the "Beta Update" file to get it to the latest version.  This saves them from having to make several (or many) install builds and can just provide a patch from your version to the latest version, but it can be confusing.  The latest version of FE beta is 0.77.  The base version is 0.75.

Hope this helps!