GROND images of the GRB 080523 X-ray afterglow position (black circle), showing the optical afterglow (left, red circle) from the first night’s r′-band observation (as given in Table A.2), the r′-band observation 6 yrs later demonstrating the fading of the afterglow (middle), and the g′-band observation of the same epoch showing the strong blue colour of the emission directly underneath the afterglow position, consistent with a putative host galaxy.