src/config.c Modified

@@ -105,7 +105,7 @@
     { "set_mark", &set_mark, NULL },
     { "go_to_mark", &go_to_mark, NULL },
     { "toggle_fullscreen", &toggle_fullscreen, NULL },
-    { "halfimize", &halfimize, NULL },
+    { "halfimize", &halfimize, &dir_handler },
     { "reload_config", &reload_config, NULL },
 };
 

src/action.c Modified

@@ -242,10 +242,11 @@
 
 
 void halfimize(struct server *server, void *data) {
-    struct view *view = wl_container_of(server->current_desk->views.next, view, link);
-    if (!view)
+    if (wl_list_empty(&server->current_desk->views))
 	return;
 
+    struct view *view = wl_container_of(server->current_desk->views.next, view, link);
+
     if  (server->current_desk->fullscreened == view->surface)
 	fullscreen_xdg_surface(view, view->surface, NULL);