The bug

When you push a target block with arrows in it, the arrows remain floating as if placed on an invisible block.

To reproduce

1. Shoot an arrow at a target block
2. Move the target block with a piston
   → The arrow will move correctly along with the target block
3. Retract the piston
   → The arrow will not move and stay floating in the air
4. Extend the piston again
   → The arrow is moved one block further, still stuck floating in the air
5. Retract the piston again
   → The arrow now falls to the ground

Video

Minecraft 20w11a - Singleplayer 2020-03-14 13-01-47.mp4