When holding firework rockets in my off hand, and nothing in my main hand, when I right-click a charged Respawn Anchor to set it as my spawn point, a rocket is used in addition to my spawn point getting updated.
I know this was already corrected in a previous snapshot for when they're held in the main hand, but it seems the problem still exists with the off hand.
In case it wasn't clear, this is in the Nether. When doing so in the Overworld, a rocket is not consumed and the Anchor explodes as expected.