Periodogram of the radial velocities (top) and activity indices (middle), along with the window function of the observations (bottom) for the FEROS data of TOI-375. False-alarm probabilities are indicated by horizontal lines: dashed red for 1% FAP and dotted blue for 0.1% FAP in each panel. The green vertical lines mark peaks in the radial-velocity periodogram with a FAP below 1% or corresponding to a confirmed a priori planetary signal, such as the 9.4-day signal. In contrast, the magenta vertical lines indicate signals that are unlikely to be of planetary origin.