The Bug:

Players' arms that are used to charge crossbows and hold loaded crossbows naturally bob.

Just for clarification, "bob" refers to the natural swaying motion of the model parts. When using spyglasses, players' arms do not bob, therefore one would expect the same behavior to occur when charging crossbows and holding loaded crossbows.

Steps to Reproduce:

1. Switch to creative mode and obtain a crossbow.
2. Charge the crossbow and observe if your arms naturally bob as you do this.
3. Hold the loaded crossbow and observe if your arms naturally bob.
4. Take note as to whether or not players' arms that are used to charge crossbows and hold loaded crossbows naturally bob.

Observed Behavior:

Players' arms that are used to charge crossbows and hold loaded crossbows naturally bob.

Expected Behavior:

Players' arms that are used to charge crossbows and hold loaded crossbows would not naturally bob.