Left panel: integrated intensity map of HCO (2_2,1 –1_1,1). The error on the integrated intensity is 0.01 K km s⁻¹. The black contours represent increasing 10% steps of the CH₃OH column density map, derived as explained in Sect. 4.1. The pink circle marks the C¹⁷O peak (see also Fig. 4). Middle panel: integrated intensity maps of HDCO (2_1,1 –1_1,0). The error on the integrated intensity is 0.005 K km s⁻¹. The black contours represent 10% steps with respect to the deuterated methanol column density peak. Right panel: integrated intensity map of D₂CO (2_1,2 –1_1,1). The error on the integrated intensity is 0.01 K km s⁻¹. The black contours represent 10% steps with respect to the deuterated methanol column density peak. In all panels, the beam is shown in the bottom right corners, and the black cross marks the dust continuum peak. Only pixels with detection levels above 3σ are included.