I'm getting the following error when I try to play a game on the pogo.com website. I had some problems with Adobe Flash, but had fixed them with something I found at the help center. I'm not sure if this is related to flash or not.

Context3D not available! Possible reasons: wrong wmode or missing device support.
I'm using Ubuntu 18.04 LTS, & FireFox 60.0.2 (64-bit). Anyone know how to fix this?