Forum Chess Puzzle Graphics Error

Overview: 

The daily puzzle today has a graphics error. When I click on a piece and drag it off the bottom side of the puzzle, it doesn't stay on the bottom side, but "pops up" about ten pixels.

Environment: 

Browser: Safari

Webpage: https://www.chess.com/forum/view/daily-puzzles/11-18-2017-halberstadt-ce-soir-1937

Operating System: Mac 

Steps to Reproduce:   

Two ways to do it.

1. Go to link above. Click on the daily puzzle. Click on a piece, and drag it off the bottom edge of the puzzle. The error will be reproduced.

2. Try it right here.

*Note: It might work on this page, because I can't see the puzzle until after I post it.

Result: 

Here's a video:

Expected Result: 

The piece should have stayed at the bottom of the board instead of "popping back up".

Here's a link to the video on Google Drive. https://drive.google.com/file/d/13Ar-ANuCfO1trSaUJybrSmkmXoUje097/view?usp=sharing 

I'm pretty sure I've seen something similar to this on the non-beta version of this site as well (Mac / Chrome v62) for all chess puzzles.