diff --git a/src/win.c b/src/win.c
index 023aacc5..1bfa1d79 100644
--- a/src/win.c
+++ b/src/win.c
@@ -757,7 +757,7 @@ wid_get_prop_wintype(struct x_connection *c, struct atom *atoms, xcb_window_t wi
 
 	for (unsigned i = 0; i < prop.nitems; ++i) {
 		for (wintype_t j = 1; j < NUM_WINTYPES; ++j) {
-			if (get_atom_cached(atoms, WINTYPES[j], strlen(WINTYPES[j])) ==
+			if (get_atom_with_nul(atoms, WINTYPES[j], c->c) ==
 			    (xcb_atom_t)prop.p32[i]) {
 				free_winprop(&prop);
 				return j;