Since version >3.12, the contents of gnome-icon-theme has now moved to adwaita-icon-theme. Epiphany should update its dependencies to "|| (>=x11-themes/adwaita-3.14.1 >=x11-themes/gnome-icon-theme)", or perhaps drop the dep on gnome-icon-theme completely if that package is going to be removed soon Reproducible: Always
Oh, and s/Epiphany/lightdm-gtk-greeter in the bug description. I filed a similar bug against Epiphany and did some copy-paste :)
So perhaps something like || (>=x11-themes/adwaita-3.14.1 x11-themes/gnome-icon-theme) is what's needed
Thanks. Fixed