Sorcerer's Teleport on left click casts when targeting monsters

Expected behavior: when Teleport (or any other defensive skill) is assigned to the left mouse button, it should only cast if Hold (i.e. default Shift) is held while clicking.

Actual behavior: Teleport casts if you mouse over an enemy and use any other ability while holding left click.

Steps to reproduce:

  • Assign Teleport to left-click
  • Assign Chain Lightning to 1
  • Hold left mouse button and then hover over an enemy
  • Notice that Teleport doesn’t cast
  • Press 1 to use Chain Lightning, continuing to hold left mouse over the enemy
  • Teleport unexpectedly casts

A lesser version of this problem is that if you click on an enemy, it causes Teleport to cast. It doesn’t cast if you’ve already clicked down before moving your mouse to the enemy, unless you then cast a spell.

I’m assuming this is because Teleport deals damage, but this behavior is inconsistent with previous Diablo games and virtually every other game in the genre.