I don't have arcade or natural. I am currently on walnut, so I will try something else.
Walnut is not an animation. It's a theme/board type.
If you play on the website, you can see your animation setting here:
https://www.chess.com/settings/board
Thank you, Brunnhilde. Unfortunately I only have access to my tablet (an Amazon fire) and the only browser it allows me to access is silk. I have tried accessing other browsers but I get a message that this browser is not supported by the device. 😐
I have Animationtype MediumDefault already, never any other. Still suffering unwanted bisschops. Could some Flash or javascript version be the culprit? The trouble started when C.c "improved" the user interface the last time. Gods knows what they changed else behind the scenes. I think any site should state the demand (minimum operating system, flash, amount memory etc) especially after an "improvement". Luckily i did not yet take a payed account last year, when C.c started the Bishoptyranny.
I "fixed" the promotion bug by changing to playing on a more mainstream and modern browser. You may wish to check which browser you're using and what version. Chess.com used to work fine on a non-mainstream (i.e. not Firefox, Chrome, Safari, etc.) browser I prefer to use, but this bug basically forced me to switch to Firefox whenever I wanted to play chess. It really just came down to Chess.com not playing well anymore with more obscure browsers.
Note: I am using a laptop, not a mobile device.