Real-space normalized MFs determined from the Planck 2018 temperature data using the four component-separated maps, Commander (red), NILC (orange), SEVEM (green), and SMICA (blue). The grey region corresponds to the 99th percentile area, estimated from the FFP10 simulations processed by the SMICA method, while the dashed curves with matching colours outline the same interval for the other component-separation methods. Results are shown for analyses at N_side = 32, 256, and 1024. The right-most column shows the χ² obtained by combining the three MFs in real space with an appropriate covariance matrix derived from FFP10 simulations. The vertical lines correspond to values from the Planck data.