Using the /setblock or the /fill commands in the end dimension to force a nether portal block to spawn will send the player to the overworld at world spawn and y-level 32,768. This also causes the world to permenamtly lag out, preventing many interactions, random tick updates, and block updates. Although it is difficult to come across this bug unintentionally, and impossible to pull off in survival mode without cheats, it is still quite inconvenient.