Top-left panels: Resolved maps of the polarization angle and fraction of W0204-0506 measured with FORS2. Polarization values are shown for every pixel where the combined flux from all PSF-matched o- and e-beam images is detected above 5σ. Top-right panels: HST/WFC3 images in the F555W and F160W bands. All cutouts have a size of 3″ × 3″ and have been astrometrically aligned using stars within the field of view. The cross shows the position of the brightest F160W pixel in all panels. The dashed cyan-black lines in all top panels mark the edges of a cone with ψ_Cone = 40 deg and an axis length of 10 kpc projected by the 60 degree inclination of the model (see Sect. 4 for details). Bottom: Representative best-fit model intensity and polarization maps, convolved with the FORS2, F555W, or F160W PSF as appropriate. The cross shows the position of the quasar.