When summoning an item frame with /summon, while using the coordinates of a non-air block, causes z-fighting between the block and the item frame..
Possibly relates to MC-123221, MC-138358 and MC-161583.
Levers on top of item frames z fighting with blocks in item frames
Putting an item frame with an anvil on the item frame on the same block as where a torch is causes Z-Fighting
Item frames placed on the ground z-fight with pressure plates / rails / carpets