When placing water above the altar, the ender dragon is unable to perch and remains in a loop of spinning around the altar.

Steps to reproduce

• Enter the end

  /execute in minecraft:the_end run tp @s 0 100 0

• Place water above the altar. I used the following setup to consistently replicate it. Do not place water directly above the center of the altar as that leads to MC-207174

• Wait until the dragon perches and observe that it starts spiralling around the altar instead of landing above the center block.