Protoplanet trajectories (solid lines) for one realisation of the fiducial model. The water snowline (depicted by the dashed blue line) is located at around 0.1 au and moves outwards in time due to a decreasing icy pebble flux. Shaded regions depict background planetesimal densities (the protoplanets are not accounted for in these background planetesimal densities). The first planetesimals form after ~ 10³ yr. The colour of the solid lines corresponds to the eccentricity of that protoplanet: the redder, the more eccentric its orbit; the blacker, the more circular. The line width is proportional to protoplanet mass.