Distribution of H I-selected Coma galaxies (coloured circles) and the field galaxy reference sample (hexagonal bins) in the stellar mass – atomic gas fraction plane. Red line shows our best-fit linear relation to the SFMS galaxies (defined using Fig. 7) in the reference sample. Black crosses mark Coma galaxies with tails at H_α or UV wavelengths, while red circles denote ongoing AGN activity. Black errorbars are the mean uncertainties of the Coma measurements. The cyan and magenta diamonds indicate the median gas fractions measured by Catinella et al. (2018) and Healy et al. (2019), respectively.