diff --git a/src/main.c b/src/main.c
index a952ba2b..947c783b 100644
--- a/src/main.c
+++ b/src/main.c
@@ -378,7 +378,7 @@ int main(int argc, char *argv[]) {
 #include "atoms.xmacro"
 #undef xmacro
     };
-    xcb_change_property(conn, XCB_PROP_MODE_REPLACE, root, A__NET_SUPPORTED, A_ATOM, 32, 16, supported_atoms);
+    xcb_change_property(conn, XCB_PROP_MODE_REPLACE, root, A__NET_SUPPORTED, A_ATOM, 32, 15, supported_atoms);
     /* Set up the window manager’s name */
     xcb_change_property(conn, XCB_PROP_MODE_REPLACE, root, A__NET_SUPPORTING_WM_CHECK, A_WINDOW, 32, 1, &root);
     xcb_change_property(conn, XCB_PROP_MODE_REPLACE, root, A__NET_WM_NAME, A_UTF8_STRING, 8, strlen("i3"), "i3");