When firing an arrow next to a fence or wall from above, the arrow will catch on the fence/wall if it's shot at a steep enough angle. Fences/walls have a hitbox of 1.5 blocks, however one would expect to be able to shoot arrows over a fence/wall since visually it's only one block tall. Regardless of that opinion; you can still shoot an arrow through the top 0.5 blocks of their hitbox at a flat angle which does indeed make this a bug either way.
This issue was not present in 1.13 and only became a problem somewhere on the road to the 1.14 update. I strongly urge that this be fixed, being able to shoot down from fences/walls is incredibly useful in an extremely large variety of situations.
I have attached images that show the unexpected behavior and images that show arrows passing over fences through the top 0.5 blocks of their hitbox if shot horizontally.
Steps to reproduce:
Place down some walls (the issue is most noticeable with walls but it occurs with fences too)
Stand up against the wall
Shoot an arrow at a steep downwards angle while still aiming above the wall
For best results stand on a half slab
Can confirm in 20w51a. This issue only occurs from shooting at the fence from certain angles.