To download all objects using wget:

wget -r -H -N --cut-dirs=7 --include-directories="/v1/" "https://swiftbrowser.dkrz.de/public/dkrz_1e33ba3a-9ecb-452f-93b9-583cf4a66e57/ICON-HDCP2-DE/20130420/20130420-default/SEVIRI_Synthetic_VISOP/06UTC/?show_all"

Name
refl_sat_model_SEVIRI_VIS006.png
refl_sat_model_SEVIRI_VIS008.png
refl_sat_model_SEVIRI_rgb68.png
refl_sat_obs_SEVIRI_VIS006.png
refl_sat_obs_SEVIRI_VIS008.png
refl_sat_obs_SEVIRI_rgb68.png