diff --git a/src/run/display/x11.cr b/src/run/display/x11.cr
index 5aa7cf9..d9ea441 100644
--- a/src/run/display/x11.cr
+++ b/src/run/display/x11.cr
@@ -293,7 +293,7 @@ module Run
 			_key_event.type = type
 			_key_event.keycode = keycode
 			_key_event.state = state
-			if keycode <= 9 # mouse button
+			if type >= 4 # mouse button. keycode will be 1-9
 				# pretend that keysym = keycode
 				@key_handler.not_nil!.call(_key_event, keycode.to_u64, nil)
 			else
diff --git a/tests.ahk b/tests.ahk
index e152b67..89d9fe5 100755
--- a/tests.ahk
+++ b/tests.ahk
@@ -3,7 +3,7 @@
 ; Right now, only commands that can be easily tested in 1-2 lines are tested.
 ;;;;;;;;;;;;;;;;;;;;;;
 
-N_TESTS = 48
+N_TESTS = 50
 
 GoSub, run_tests
 if tests_run != %N_TESTS%
@@ -633,6 +633,28 @@ runwait, xdotool key shift+s
 expect = hotkey shift_s lowercase,hotkey_shift_s_success,1
 gosub assert
 
+; esc and xbutton2 share the same keycode:
+goto l_after_esc_hotkey
+			hotkey_esc:
+				hotkey_esc_success = 1
+			return
+l_after_esc_hotkey:
+hotkey, esc, hotkey_esc
+runwait, xdotool key Escape
+expect = hotkey esc,hotkey_esc_success,1
+gosub assert
+hotkey, esc, off
+goto l_after_xbutton2_hotkey
+			hotkey_xbutton2:
+				hotkey_xbutton2_success = 1
+			return
+l_after_xbutton2_hotkey:
+hotkey, xbutton2, hotkey_xbutton2
+runwait, xdotool click 9
+expect = hotkey xbutton2,hotkey_xbutton2_success,1
+gosub assert
+hotkey, xbutton2, off
+
 Send, {LButton}
 sleep 20
 expect = send {lbutton},gui_button_clicked_success,1