A new worse version of MC-159757. Not only are Endermen unable to move when looked at (when they are already hostile, not neutral), but they are now also unable to teleport as well. (They will now teleport if you get too close, or try to hit them though -20w28a)
Half-fixed in 20w28a. They can no longer be damaged when frozen, since they teleport away before any damage is dealt. You can still abuse this bug to hide/escape from Endermen by keeping your crosshair locked onto their face while walking backwards.
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Affects 1.16 and 1.16 Release Candidate 1