cancelevent ~onUse not working for offhand block based items

Example of issue is to have a carved pumpkin (intended to be used as a hat), and giving it these skills with no conditions:

  Skills:
  - skill{s=wearhat} ~onUse
  - cancelevent{sync=true} @self ~onUse

In the mainhand slot, it will correctly prevent placing the pumpkin, however in the offhand slot the placement event is not cancelled. Other skills will run if you do not specify a slot condition whether it be in offhand, mainhand, or armor slots by default, so this appears to be a bug or unintended result of a change in Crucible(?) where mythic items are placeable; in which they were not before. Running current MM dev and Crucible dev builds as of writing.