Extended Tracking mode icon is not displaying.

I'm going to answer my own question, after a couple of days of struggling to resolve this issue.  Apparently my firmware in the mini really did not update from v2.20 to v2.60 , so that's why the XT icon wouldn't appear!  My mistake was running the Garmin Sync app right after doing the firmware update from Garmin Express. This somehow interfered with the firmware update process, yet Garmin express kept telling me that my mini was updated, even though it wasn't. (The "About This Device" screen on the mini said firmware v2.20, but Garmin Express said the device had v2.60. Weird.)  Lesson to be learned: The correct thing to do after downloading the firmware update on Garmin Express is to disconnect the mini from the computer and then let the mini restart.  Don't run the Garmin Sync app immediately after downloading the update from Garmin Express.