Why are my animation blueprints constantly having the thumbnails generated?

At some point in the recent past my 5 Maximo pawn’s animation blueprints are constantly requiring to be saved. I have not been doing any changes around the pawns animation. The log below says that the thumbnails are being generated. In fact, 2 of them I have not touched at all since moving them to my projects directory.

Is it something to do with the autosave?

LogFileHelpers: Editor autosave (incl. sublevels) for '/Game/x/Maps/IslanTime_P' took 0.025
OBJ SavePackage: Generating thumbnails for [1] asset(s) in package [/Game/x/Pawns/Mixamo_Alpha/Anims/MixamoAnimBP_Alpha] ([1] browsable assets)...
OBJ SavePackage:     Rendered thumbnail for [AnimBlueprint /Game/x/Pawns/Mixamo_Alpha/Anims/MixamoAnimBP_Alpha.MixamoAnimBP_Alpha]
OBJ SavePackage: Finished generating thumbnails for package [/Game/x/Pawns/Mixamo_Alpha/Anims/MixamoAnimBP_Alpha]
LogSavePackage: Save=162.46ms
LogSavePackage: Moving '../../../../Development/x/Saved/MixamoAnimBP_Alpha_Auto1D6EA54274FD86133942EB2BBD8FFC37B.tmp' to '../../../../Development/x/Saved/Autosaves/Game/x/Pawns/Mixamo_Alpha/Anims/MixamoAnimBP_Alpha_Auto1.uasset'
LogSavePackage:Display: Finished SavePackage ../../../../Development/x/Saved/Autosaves/Game/x/Pawns/Mixamo_Alpha/Anims/MixamoAnimBP_Alpha_Auto1.uasset

I suspect something outside of UE4 was causing this. I am not using that tool/plugin for 4.17 and am I not getting this behavior anymore.