Plot of the residuals and the corresponding closed confidence contours plot from the blind scan of the type 1 AGN LBQS 1338−0038. Top: data/model ratio plot for the EPIC-pn spectrum (MOS 1 and MOS 2 are not included for clarity), showing the residuals in the 5–10 keV band. A broad emission and absorption profiles are seen at ∼ 6.6 keV and ∼ 8 keV, respectively, suggesting a P Cygni-like profile. The vertical lines indicate the Fe Kα laboratory transition at E_lab = 6.40 keV (lime green) and Fe XXV and Fe XXVI at E_lab = 6.70 keV and 6.97 keV, respectively (magenta). The outer to inner closed contours correspond to a Δ𝒞 significance of (−2.3 = 68%), (−4.61 = 90%), (−9.21 = 99%), and (−13.82 = 99.9%) relative to the best-fitting continuum. Bottom: corresponding blind-search contours, showing the evidence of strong emission profiles at high confidence level (see the colour bar on the right).