Turtle icon not shown in about window in flatpak
$ flatpak run de.philippun1.turtle about
(python3:3): Gtk-WARNING **: 15:03:27.372: Failed to load icon /run/host/share/icons/hicolor/scalable/apps/de.philippun1.turtle.svg: Error opening file /run/host/share/icons/hicolor/scalable/apps/de.philippun1.turtle.svg: No such file or directory