For unknown reason I can't delete this lamp, even if I buldoze the lot, it's still there.
#Can't delete an object in Buid mode
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shell grail
try going back to main menu and going back into your save, that usually deletes the item for me
tranquil flax
I had the same issue just now, and reloading also worked for me
low barn
its a visual bug, i have noticed it occurring when placing items via the Inventory (if you click the "Place" button while in the middle of placing an object, it leaves a "ghost" of the object you were placing)