Popup (show the control in modal form) in the center of the screen relative to the current canvas transform, clamping the size to size, then ensuring the popup is no larger than the viewport size multiplied by fallback_ratio.
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Popup (show the control in modal form) in the center of the screen relative to the current canvas transform, clamping the size to size, then ensuring the popup is no larger than the viewport size multiplied by fallback_ratio.