GLS periodogram and photometric time series of the TESS light curve for TOI-263. Top: GLS periodogram of the TESS light curve from Sectors 3 and 4, (binned in 3 h intervals). The dashed red line indicates a false alarm probability threshold of 10%. The highest peak in the periodogram marked with a red dot corresponds to a period of 0.5575 ± 0.0008 d. Bottom left:TESS photometric time series modeled with a sinusoidal with a period corresponding to the highest peak in the GLS periodogram above. Bottom right: TESS photometry phase-folded to the aforementioned period, in days.