Left panel: XMM-Newton energy spectra of SRGt 062340, shown with the best-fitting model (TBabs*(apec+apec+apec)). The bottom panel shows the normalised residuals. The best-fit parameters are listed in Table 4. Top right panel: Zoomed-in image of the Fe K complex, fitted with a TBabs*(apec+gaussian) model. The dashed lines represent the model components for the EPIC-MOS1 spectrum, shown as an example. The vertical dotted lines mark the expected energies of the different Fe-line components. Bottom right panel: RGS spectrum and best-fitting model, identical to those shown in the left panel, but plotted as a function of wavelength. The vertical lines indicate several prominent and commonly observed transitions.