Continuum-normalised LDSS3 spectrum of J0921+0007. The size of the proximity zone is defined here as the proper distance between the rest-frame wavelength of Lyα (dashed orange line) and the wavelength where the smoothed continuum normalised flux (solid red line) first drops below 0.1% of its extrapolated value, marked here by a solid green line. The unsmoothed continuum-normalised spectrum is shown in black.