I am not sure how to remove the readout component completely, but to replace it you can use
firefly.util.image.initAutoReadout(readoutComponent, props). To see how to use it, search for
firefly.util.image.initAutoReadout(props => null) to see if it will remove the component completely, but I still see an empty closable popup, when the mouse is over an image. Maybe Trey @roby has more info on how to remove the readout component completely.