So I’ve been looking at this issue and it seems like there is a fundamental issue with iframes and not properly firing pointerout or pointerleave events, which would be needed to “let go” of the mouse button. As far as using pointerlock as a workaround, I created a PR to address the error that comes up so you should be able to use pointerlock without issue: DeviceInputSystem: Catch pointer capture calls during pointer lock by PolygonalSun · Pull Request #11120 · BabylonJS/Babylon.js (github.com)