diff --git a/include/wlr/types/wlr_seat.h b/include/wlr/types/wlr_seat.h
index 588bdc63..2f5fd31b 100644
--- a/include/wlr/types/wlr_seat.h
+++ b/include/wlr/types/wlr_seat.h
@@ -116,7 +116,7 @@ struct wlr_keyboard_grab_interface {
 	void (*key)(struct wlr_seat_keyboard_grab *grab, uint32_t time_msec,
 			uint32_t key, uint32_t state);
 	void (*modifiers)(struct wlr_seat_keyboard_grab *grab,
-			struct wlr_keyboard_modifiers *modifiers);
+			const struct wlr_keyboard_modifiers *modifiers);
 	void (*cancel)(struct wlr_seat_keyboard_grab *grab);
 };
 
@@ -541,7 +541,7 @@ void wlr_seat_keyboard_notify_key(struct wlr_seat *seat, uint32_t time_msec,
  * any keyboard grabs.
  */
 void wlr_seat_keyboard_notify_modifiers(struct wlr_seat *seat,
-		struct wlr_keyboard_modifiers *modifiers);
+		const struct wlr_keyboard_modifiers *modifiers);
 
 /**
  * Notify the seat that the keyboard focus has changed and request it to be the
diff --git a/types/data_device/wlr_drag.c b/types/data_device/wlr_drag.c
index c1fa801b..f0b6cfa6 100644
--- a/types/data_device/wlr_drag.c
+++ b/types/data_device/wlr_drag.c
@@ -326,7 +326,7 @@ static void drag_handle_keyboard_key(struct wlr_seat_keyboard_grab *grab,
 }
 
 static void drag_handle_keyboard_modifiers(struct wlr_seat_keyboard_grab *grab,
-		struct wlr_keyboard_modifiers *modifiers) {
+		const struct wlr_keyboard_modifiers *modifiers) {
 	//struct wlr_keyboard *keyboard = grab->seat->keyboard_state.keyboard;
 	// TODO change the dnd action based on what modifier is pressed on the
 	// keyboard
diff --git a/types/seat/wlr_seat_keyboard.c b/types/seat/wlr_seat_keyboard.c
index a8d79c79..65acec33 100644
--- a/types/seat/wlr_seat_keyboard.c
+++ b/types/seat/wlr_seat_keyboard.c
@@ -25,7 +25,7 @@ static void default_keyboard_key(struct wlr_seat_keyboard_grab *grab,
 }
 
 static void default_keyboard_modifiers(struct wlr_seat_keyboard_grab *grab,
-		struct wlr_keyboard_modifiers *modifiers) {
+		const struct wlr_keyboard_modifiers *modifiers) {
 	wlr_seat_keyboard_send_modifiers(grab->seat, modifiers);
 }
 
@@ -321,7 +321,7 @@ bool wlr_seat_keyboard_has_grab(struct wlr_seat *seat) {
 }
 
 void wlr_seat_keyboard_notify_modifiers(struct wlr_seat *seat,
-		struct wlr_keyboard_modifiers *modifiers) {
+		const struct wlr_keyboard_modifiers *modifiers) {
 	clock_gettime(CLOCK_MONOTONIC, &seat->last_event);
 	struct wlr_seat_keyboard_grab *grab = seat->keyboard_state.grab;
 	grab->interface->modifiers(grab, modifiers);
diff --git a/types/xdg_shell/wlr_xdg_popup.c b/types/xdg_shell/wlr_xdg_popup.c
index 184c03fd..4e0fae10 100644
--- a/types/xdg_shell/wlr_xdg_popup.c
+++ b/types/xdg_shell/wlr_xdg_popup.c
@@ -121,7 +121,7 @@ static void xdg_keyboard_grab_key(struct wlr_seat_keyboard_grab *grab, uint32_t
 }
 
 static void xdg_keyboard_grab_modifiers(struct wlr_seat_keyboard_grab *grab,
-		struct wlr_keyboard_modifiers *modifiers) {
+		const struct wlr_keyboard_modifiers *modifiers) {
 	wlr_seat_keyboard_send_modifiers(grab->seat, modifiers);
 }