Upper panel: radial velocity measurements and FWHM of CCF for VX Sgr from the STELLA telescope compared to V and visual light curves from AAVSO. The data show similar behavior to that of Betelgeuse (Kravchenko et al. 2021; Jadlovský et al. 2024), namely, the double-shock feature in the FWHM plot before the likely mass-loss event. Lower panel: Hα for selected STELLA spectra showing the emergence of the emission component during the 2020–2021 event.