I completed two Mining activities, clicked both of them to claim the rewards, and while they were still in the process of claiming (slight computer lag) I sent my mining wolf to the Grotto. Next thing I knew I had 8 activities, not the usual 6. Hard refresh did not remove the two extras.
Upon completing an activity it went away without being replaced, leaving me with 7. Completion of a second activity left me with 6 activities and normal behavior resumed.
