Time histories of the Solar Orbiter/STIX and GOES/XRS fluxes and the isothermal parameters, temperature, and emission measure for all selected events. From top to bottom, the events are sorted by duration of the onset interval: SOL2021-09-23, SOL2021-05-07, SOL2021-10-09, and SOL2022-03-11. From left to right, we show the time evolution of the STIX and GOES fluxes, time profiles of the temperature and emission measure, and the correlation plot of the temperature as a function of the emission measure. The gray areas in the leftmost panels indicate the accumulation interval selected for producing the STIX images of Figs. 3–6. The horizontal black lines in the plots of the first two columns indicate the spectral model used at different times: purely isothermal (solid, TH) or isothermal with an additional nonthermal component (dotted, TH+NTH). The STIX emission measure–temperature color coding in the rightmost column matches that of the temperature time series in the central column.