ALMA spectrum of GLASS-z13, extracted from the uv-tapered cube (with a taper of 0.6 arcsec). The spectrum was created by extracting the flux density within a circular aperture with a diameter of 1 arcsec around GLASS-z13. The orange bars indicate the spectrum, whereas the grey dashed lines correspond to the 1-σ noise limit of the data. No emission line is detected within the spectrum.