Putting a Repeated command block with "tp @e[type=minecraft:skeleton] 0 0 5" in it creates a visual glitch, copy of the same entity that is teleporting to that coordinates. The copy stays at the previously position of the entity and acts like he is on the same coordinate as the real one (probably because it has same UUID), the copy cannot be pushed, either be hit.
Also if you do this command: "/execute at @e[type=minecraft:skeleton] run setblock ~ ~2 ~ minecraft:obsidian keep", it will won't work for ghost entities.
The attachment is too big, so here's posted on youtube (unlisted):
https://youtu.be/KhwOhopdhws
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However, this issue is a Duplicate of MC-127457.
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