Predictions from EvCon models for SEDs including nebular emission (solid curves) and purely stellar SEDs (dashed curves) for the parametric SFHs in Fig. A.1. Zero intrinsic extinction and attenuation by the intergalactic medium have been assumed throughout. a: Variation δμ′ (U mag) of the reduced surface brightness μ′. The arrow and bullet mark the z at which the Lyα (1216 Å) line and the LyC edge (912 Å) enter the blue edge of the U filter (1.508 and 2.34, respectively). b: bulge-to-disk surface brightness contrast δμ_BD (U mag) when assuming the contSF SFH scenario for the disk. c: ObsF U-B color. The evolution of the rest-frame color for the contSF and τ0.5 SFH scenario is shown by the purple solid and dotted curve, respectively). d: ObsF bulge-to-disk color contrast in U-B. The meaning of panels e–h is analogous.