in harrati hinterlands there are those 2 heart in the northwest part of the map that lets you collect tags from those poles with skeleton heads on them. fill your invent so its full and keep hitting f next to the pole wont get you the item but will fill the bar. game sees it that you didnt get item so you can get it again.
both hearts done in 2 sec total!! i know its a small bug but i guess it works that way with every collect heart