Liliana’s new escape hatch is nice, and indeed GDK_PIXBUF_MODULE_FILE is unset in
$ guix shell --pure viewnior webp-pixbuf-loader $ echo $GDK_PIXBUF_MODULE_FILE but it rebuilds the world. A security-relevant (?) upstream introduction of GDK_PIXBUF_MODULE_PATH also would have Guix rebuild the world. Could I, with your agreement, push the viewnior wrapper patch with (wrap-program viewnior `("GDK_PIXBUF_MODULE_FILE" = in the meantime? The majority of users will not know search paths anyway perhaps, and viewnior is just one image viewer. Regards, Florian