[Fixed in 1.14] Hand disappears when gliding with elytra in first person view

The 1.13 betas introduced some animation/positioning issues:

1. Your hand will be displayed in weird positions when you start gliding with an elytra (only when facing north or south);

Expected results:
The hand position/animations look exactly like it did before, which was at parity with Java.

Observed results:
Although Bedrock doesn't have to be exactly like Java, this is broken.