On a very slow machine, in the gallery when I scroll horizontal, sometimes the previous thumbnail is half visible and so the method eog_thumb_view_clear/add_range is called repeatedly and load/unload this range.
The commit 94e2029e fix this problem by only unloading the second previous thumbnail. That mean :
|we unload this thumbnail||Still loaded||The first visible thumbnail|
|Image 1||Image 2||Image 3|