Visualization of the selection for SMBHB candidates based on their SRG/eROSITA light curves. Top panel: Observed counts at the position of the source eRASSt J0530-4125 (see Table 1) at every SRG/eROSITA scan in the 0.2–2.3 keV energy band. Each image is temporarily spaced every six months. The white circles correspond to a typical aperture with a radius of 30″, similar to the scale bar displayed on the bottom right side of each panel. Lower panel: X-ray light curve of eRASSt J0530-4125. The colored arrows indicate the significance of the flux change between the consecutive scans. The blue-shaded areas indicate the bright and faint flux levels of the source, while the purple arrow shows the factor and significance between these two flux levels.