The Respawn Anchor cannot be charged via a Hopper.

1. Place a Respawn Anchor in your world, and place a Hopper facing it.

2. Put Glowstone into the Hopper.

Expected result: The item in the Hopper is consumed, and the Respawn Anchor is successfully charged.

Actual result: The item in the Hopper is not consumed, and the Respawn Anchor is not charged.