Early evolution of STIX X-ray sources overlaid on two EUI/FSI 174Å images. Contours indicate 50 and 90 % levels of the peak flux in the STIX images, all times on images are on board times. Top row: X-ray sources of possible thermal origin up to 25 keV which are close to the FSI image taken at 13:10 on board time (13:16 UT). Bottom row: Subsequent times, closer to the FSI image taken at 13:20 on board time (13:25 UT), when the 16–25 keV source is of non-thermal origin.