Loading in-game resulting in a grey screen [CLIENT]

Upon entering a game, I'm being greeted by a blank, grey screen. I can't seem to escape in any other way than simply just restarting my laptop. (Macbook Pro, 2015, i5, Version 10.14.6)

I'm not entirely sure what to do, but since clash is coming really soon, I'd really like to play with my team. It seems as though the game continues in spite of my grey screen though, as I've been given a loss while experiencing this issue on another account.

Upon checking the boards for another such error, the fix was to update to macOS 10.14.4, however, I'm already past that. As such I'm stumped.