Website view only half screen in Chrome (content left and blank white to right)

Question

Wondering if anyone else has had this bug, which I've only seen in Chrome where the page is only visible in the left half of the browser?

See the attached image where I have left the scrollbar visible so you can see the additional whitespace - to the right. Also stops scrolling after a certain point so content below what is first visible is not in view.

Strangely, this problem resets itself when you change tab or open the inspector tool and then it resets itself. Until page reloads again.

Upon disabling all JS and CSS there is the exact same result.

Nothing special or different about the meta tags i.e.

<meta name="viewport" content="width=device-width, initial-scale=1.0">

Tried adding the standard width, height 100% to the html,body. Nothing - no different.

So is this just a problem in Chrome (both on Mac and Windows)?

Any advice I'd be very grateful for because it's driving me insane.