Relation (or lack thereof) between the extension in RG1 (here described by the major axis of the ellipses) and the spread in metallicity proposed by L22. For clarity, we show four panels with only three cases with similar spreads, as is claimed by L22, in each one. The GCs and the metallicity spreads are indicated in the plots with the same colour as the corresponding ellipse. The extensions lenRG1 are in Table 2.