Zoom-ins show two emission features detected in the VIS arm of the X-Shooter spectra. The left and right panels consist of the 1D continuum subtracted (upper), 2D (middle), and 3D (bottom) spectrograms of HeIIλ1640 with characteristic P-Cygni line profile and semi-forbidden non-resolved CIII]λλ1907,1909 line. The fitted Gaussian emission line is overplotted in blue. The 1D spectra in both panels is shown in black, error spectrum in red, and zero-level flux with the orange line. Sharp peaks notable in 1D around the CIII]λλ1907,1909 line belonging to the sky residuals are also visible in 2D and 3D spectrograms. The 1D and 2D spectrograms are displayed in rest and observed wavelength frame.