Overlay of the opacity profiles of CH (average of the two Λ-doublets, deconvolved from their respective hyperfine structure) and H₂O (scaled by the opacity ratio γ_τ), on top of their common fit profile (see Sect. 4.2) for PKS 1830−211(NE) (top, 2012 data), the isolated velocity component near v ∼ +170 km s⁻¹ toward PKS 1830−211(SW) (middle, average of the 2016 data), and B 0218+357(SW) (bottom). Note the span of two orders of magnitude between the optical depths of these features.