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I've just hit this problem in Chrome 68 on Linux (Ubuntu 18.04 LTS). Guess it's still neither fixed nor documented?

I have a laptop with a touchscreen and 2 external monitors, trying to use ESA Sky on one of the external monitors (not a touchscreen) but every time my mouse pointer enters the browser window it pans the image. Worse, there's no way for me to disable my touchscreen to work around the issue. Not without editing X.Org config files, anyway.