Swift/XRT soft X-ray flux (top panel) and the X-ray hardness ratio R (bottom panel), plotted vs. the Swift/UVOT UVW2 filter flux. The X-ray spectral hardness ratio (R) is defined as R = (H − S)/(H + S), where H and S are the Swift XRT count rate fluxes in the hard (1.5–10 keV) and soft (0.3–1.5 keV) bands, respectively. The displayed data span from 2007 to 2022. The data corresponding to the 2022 January ToO event are indicated with a magenta circle. The Spearman's rank correlation coefficient (r _s ) and the corresponding null hypothesis p-value probability (p _null) from the two-sided t-test are given in each panel. There is a significant positive correlation between the soft X-ray and UV fluxes (top panel), and a significant negative correlation between the hardness R and the UV flux (bottom panel).