diff --git a/include/x.h b/include/x.h
index 2d41b437..afc1645c 100644
--- a/include/x.h
+++ b/include/x.h
@@ -117,4 +117,12 @@ void x_set_i3_atoms();
  */
 void x_set_warp_to(Rect *rect);
 
+/**
+ * Applies the given mask to the event mask of every i3 window decoration X11
+ * window. This is useful to disable EnterNotify while resizing so that focus
+ * is untouched.
+ *
+ */
+void x_mask_event_mask(uint32_t mask);
+
 #endif
diff --git a/src/resize.c b/src/resize.c
index a4e4dfa0..a1897b6c 100644
--- a/src/resize.c
+++ b/src/resize.c
@@ -58,6 +58,9 @@ int resize_graphical_handler(Con *first, Con *second, orientation_t orientation,
     Con *output = con_get_output(first);
     DLOG("x = %d, width = %d\n", output->rect.x, output->rect.width);
 
+    x_mask_event_mask(~XCB_EVENT_MASK_ENTER_WINDOW);
+    xcb_flush(conn);
+
     uint32_t mask = 0;
     uint32_t values[2];
 
diff --git a/src/x.c b/src/x.c
index 61824d58..e8bfaeb4 100644
--- a/src/x.c
+++ b/src/x.c
@@ -964,3 +964,19 @@ void x_set_warp_to(Rect *rect)
 {
     warp_to = rect;
 }
+
+/*
+ * Applies the given mask to the event mask of every i3 window decoration X11
+ * window. This is useful to disable EnterNotify while resizing so that focus
+ * is untouched.
+ *
+ */
+void x_mask_event_mask(uint32_t mask) {
+    uint32_t values[] = { FRAME_EVENT_MASK & mask };
+
+    con_state *state;
+    CIRCLEQ_FOREACH_REVERSE(state, &state_head, state) {
+        if (state->mapped)
+            xcb_change_window_attributes(conn, state->id, XCB_CW_EVENT_MASK, values);
+    }
+}