HST-ACS images (8″ × 8″ size) centered at the coordinates of some of our targets, as shown at the top of each image. North is up, east is left. As in Fig. A.3, NOEMA contours are shown in red, in case of CO detections. The archival HST image of A2219-1 is taken with the F850LP filter, while those of HLS sources are taken with the F818W filter. Small shifts ≤0.6 arcsec are applied to the images, consistent with GCS catalog uncertainties in the absolute astrometry used by HST.