Different rotation in HTML5 than in project

I’m rotating an actor in my project when you click and drag the mouse. Everything works as expected in engine/Package for desktop. but in html5 rotation is faster and changes direction based on the center of the screen not the direction the mouse is moving. [HTML5 Rotation - YouTube][1]

Also the rotation is way faster.
Any ideas on why this is? or how I might fix it?

Problems with models on html5 - Platform & Builds - Epic Developer Community Forums reports very similar behavior with mouse dragging.

I wonder where in the blueprints chain the issue lies. Is it possible to debug what the actual values coming from “Get Mouse X - Return Value” node are? Do things differ between native and web if printing raw values outputted from there? Or I wonder if the discrepancy is coming from some other node.