Graphical distortion in Chrome and Firefox - Only happens with second screen connected

Disconnecting my VGA monitor (running from my iGPU) and then restarting Chrome/Firefox fixes the issue completely. Reconnecting it causes it to come back.

Disabling hardware acceleration in Chrome 'fixes' the issue. I definitely want to figure out the root of the issue, however.

Distortion

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EFI

Config.plist pastebin

Specs:

Mobo: Z390-A Pro

CPU: 9600k

GPU: RX 580