diff --git a/src/handlers.c b/src/handlers.c
index 7926fec5..ad394795 100644
--- a/src/handlers.c
+++ b/src/handlers.c
@@ -558,8 +558,7 @@ static bool window_name_changed(i3Window *window, char *old_name) {
  * Called when a window changes its title
  *
  */
-static bool handle_windowname_change(void *data, xcb_connection_t *conn, uint8_t state,
-                                     xcb_window_t window, xcb_atom_t atom, xcb_get_property_reply_t *prop) {
+static bool handle_windowname_change(xcb_window_t window, xcb_get_property_reply_t *prop) {
     Con *con;
     if ((con = con_by_window_id(window)) == NULL || con->window == NULL)
         return false;
@@ -585,8 +584,7 @@ static bool handle_windowname_change(void *data, xcb_connection_t *conn, uint8_t
  * window_update_name_legacy().
  *
  */
-static bool handle_windowname_change_legacy(void *data, xcb_connection_t *conn, uint8_t state,
-                                            xcb_window_t window, xcb_atom_t atom, xcb_get_property_reply_t *prop) {
+static bool handle_windowname_change_legacy(xcb_window_t window, xcb_get_property_reply_t *prop) {
     Con *con;
     if ((con = con_by_window_id(window)) == NULL || con->window == NULL)
         return false;
@@ -611,8 +609,7 @@ static bool handle_windowname_change_legacy(void *data, xcb_connection_t *conn,
  * Called when a window changes its WM_WINDOW_ROLE.
  *
  */
-static bool handle_windowrole_change(void *data, xcb_connection_t *conn, uint8_t state,
-                                     xcb_window_t window, xcb_atom_t atom, xcb_get_property_reply_t *prop) {
+static bool handle_windowrole_change(xcb_window_t window, xcb_get_property_reply_t *prop) {
     Con *con;
     if ((con = con_by_window_id(window)) == NULL || con->window == NULL)
         return false;
@@ -956,8 +953,7 @@ static void handle_client_message(xcb_client_message_event_t *event) {
     }
 }
 
-static bool handle_window_type(void *data, xcb_connection_t *conn, uint8_t state, xcb_window_t window,
-                               xcb_atom_t atom, xcb_get_property_reply_t *reply) {
+static bool handle_window_type(xcb_window_t window, xcb_get_property_reply_t *reply) {
     Con *con;
     if ((con = con_by_window_id(window)) == NULL || con->window == NULL)
         return false;
@@ -973,8 +969,7 @@ static bool handle_window_type(void *data, xcb_connection_t *conn, uint8_t state
  * See ICCCM 4.1.2.3 for more details
  *
  */
-static bool handle_normal_hints(void *data, xcb_connection_t *conn, uint8_t state, xcb_window_t window,
-                                xcb_atom_t name, xcb_get_property_reply_t *reply) {
+static bool handle_normal_hints(xcb_window_t window, xcb_get_property_reply_t *reply) {
     Con *con = con_by_window_id(window);
     if (con == NULL) {
         DLOG("Received WM_NORMAL_HINTS for unknown client\n");
@@ -999,8 +994,7 @@ static bool handle_normal_hints(void *data, xcb_connection_t *conn, uint8_t stat
  * Handles the WM_HINTS property for extracting the urgency state of the window.
  *
  */
-static bool handle_hints(void *data, xcb_connection_t *conn, uint8_t state, xcb_window_t window,
-                         xcb_atom_t name, xcb_get_property_reply_t *reply) {
+static bool handle_hints(xcb_window_t window, xcb_get_property_reply_t *reply) {
     Con *con = con_by_window_id(window);
     if (con == NULL) {
         DLOG("Received WM_HINTS for unknown client\n");
@@ -1024,8 +1018,7 @@ static bool handle_hints(void *data, xcb_connection_t *conn, uint8_t state, xcb_
  * See ICCCM 4.1.2.6 for more details
  *
  */
-static bool handle_transient_for(void *data, xcb_connection_t *conn, uint8_t state, xcb_window_t window,
-                                 xcb_atom_t name, xcb_get_property_reply_t *prop) {
+static bool handle_transient_for(xcb_window_t window, xcb_get_property_reply_t *prop) {
     Con *con;
 
     if ((con = con_by_window_id(window)) == NULL || con->window == NULL) {
@@ -1050,8 +1043,7 @@ static bool handle_transient_for(void *data, xcb_connection_t *conn, uint8_t sta
  * toolwindow (or similar) and to which window it belongs (logical parent).
  *
  */
-static bool handle_clientleader_change(void *data, xcb_connection_t *conn, uint8_t state, xcb_window_t window,
-                                       xcb_atom_t name, xcb_get_property_reply_t *prop) {
+static bool handle_clientleader_change(xcb_window_t window, xcb_get_property_reply_t *prop) {
     Con *con;
     if ((con = con_by_window_id(window)) == NULL || con->window == NULL)
         return false;
@@ -1144,8 +1136,7 @@ static void handle_configure_notify(xcb_configure_notify_event_t *event) {
  * Handles the WM_CLASS property for assignments and criteria selection.
  *
  */
-static bool handle_class_change(void *data, xcb_connection_t *conn, uint8_t state, xcb_window_t window,
-                                xcb_atom_t name, xcb_get_property_reply_t *prop) {
+static bool handle_class_change(xcb_window_t window, xcb_get_property_reply_t *prop) {
     Con *con;
     if ((con = con_by_window_id(window)) == NULL || con->window == NULL)
         return false;
@@ -1169,8 +1160,7 @@ static bool handle_class_change(void *data, xcb_connection_t *conn, uint8_t stat
  * Handles the _MOTIF_WM_HINTS property of specifing window deocration settings.
  *
  */
-static bool handle_motif_hints_change(void *data, xcb_connection_t *conn, uint8_t state, xcb_window_t window,
-                                      xcb_atom_t name, xcb_get_property_reply_t *prop) {
+static bool handle_motif_hints_change(xcb_window_t window, xcb_get_property_reply_t *prop) {
     Con *con;
     if ((con = con_by_window_id(window)) == NULL || con->window == NULL)
         return false;
@@ -1200,8 +1190,7 @@ static bool handle_motif_hints_change(void *data, xcb_connection_t *conn, uint8_
  * Handles the _NET_WM_STRUT_PARTIAL property for allocating space for dock clients.
  *
  */
-static bool handle_strut_partial_change(void *data, xcb_connection_t *conn, uint8_t state, xcb_window_t window,
-                                        xcb_atom_t name, xcb_get_property_reply_t *prop) {
+static bool handle_strut_partial_change(xcb_window_t window, xcb_get_property_reply_t *prop) {
     DLOG("strut partial change for window 0x%08x\n", window);
 
     Con *con;
@@ -1279,7 +1268,7 @@ static bool handle_strut_partial_change(void *data, xcb_connection_t *conn, uint
 
 /* Returns false if the event could not be processed (e.g. the window could not
  * be found), true otherwise */
-typedef bool (*cb_property_handler_t)(void *data, xcb_connection_t *c, uint8_t state, xcb_window_t window, xcb_atom_t atom, xcb_get_property_reply_t *property);
+typedef bool (*cb_property_handler_t)(xcb_window_t window, xcb_get_property_reply_t *property);
 
 struct property_handler_t {
     xcb_atom_t atom;
@@ -1345,7 +1334,7 @@ static void property_notify(uint8_t state, xcb_window_t window, xcb_atom_t atom)
     }
 
     /* the handler will free() the reply unless it returns false */
-    if (!handler->cb(NULL, conn, state, window, atom, propr))
+    if (!handler->cb(window, propr))
         FREE(propr);
 }