CH₃OH(2_kk−1_kk) spectrum (in brightness temperature, T_B, scale) extracted at the blue-shifted emission peak position (see Sect. 5.3). The transitions producing the methanol profile are labelled, with the corresponding frequencies marked by vertical black segments (see Table 1). The CH₃OH spectrum is centred at the frequency of the 2_0,2−1_0,1 A transition: 96741.38 MHz. The black vertical line at +8.5 km s⁻¹ is for the systemic velocity (Podio et al. 2021). The 2_0,2−1_0,1 A and 2_1,2−1_1,1 E lines have been fit (magenta contour) by assuming for each line two Gaussian components with a FWHM of 3 km s⁻¹ shifted by −2.0 km s⁻¹, and −5.3 km s⁻¹, respectively (in blue).