--- a/src/gtkutil.c
+++ b/src/gtkutil.c
@@ -135,6 +135,8 @@ along with GNU Emacs.  If not, see <http://www.gnu.org/licenses/>.  */
 static void update_theme_scrollbar_width (void);
 static void update_theme_scrollbar_height (void);

+bool get_current_wm_state (struct frame *, Window, int *, bool *);
+
 #define TB_INFO_KEY "xg_frame_tb_info"
 struct xg_frame_tb_info
 {
@@ -1364,7 +1366,8 @@ x_wm_set_size_hint (struct frame *f, long int flags, bool user_position)
   int base_width, base_height;
   int min_rows = 0, min_cols = 0;
   int win_gravity = f->win_gravity;
-  Lisp_Object fs_state, frame;
+  int state = FULLSCREEN_NONE;
+  bool sticky = false;
   int scale = xg_get_gdk_scale ();

   /* Don't set size hints during initialization; that apparently leads
@@ -1373,13 +1376,12 @@ x_wm_set_size_hint (struct frame *f, long int flags, bool user_position)
   if (NILP (Vafter_init_time) || !FRAME_GTK_OUTER_WIDGET (f))
     return;

-  XSETFRAME (frame, f);
-  fs_state = Fframe_parameter (frame, Qfullscreen);
-  if (EQ (fs_state, Qmaximized) || EQ (fs_state, Qfullboth))
+  get_current_wm_state (f, FRAME_OUTER_WINDOW (f), &state, &sticky);
+  if (state != FULLSCREEN_NONE)
     {
-      /* Don't set hints when maximized or fullscreen.  Apparently KWin and
-         Gtk3 don't get along and the frame shrinks (!).
-      */
+      /* Don't set hints when the frame currently is maximized or
+         fullscreen.  Apparently KWin and Gtk3 don't get along and the
+         frame shrinks (!).  */
       return;
     }

diff --git a/src/xterm.c b/src/xterm.c
index b7aacfa..2e1c0b5 100644
--- a/src/xterm.c
+++ b/src/xterm.c
@@ -247,7 +247,7 @@ static void x_wm_set_window_state (struct frame *, int);
 static void x_wm_set_icon_pixmap (struct frame *, ptrdiff_t);
 static void x_initialize (void);

-static bool get_current_wm_state (struct frame *, Window, int *, bool *);
+bool get_current_wm_state (struct frame *, Window, int *, bool *);

 /* Flush display of frame F.  */

@@ -9904,7 +9904,7 @@ x_set_sticky (struct frame *f, Lisp_Object new_value, Lisp_Object old_value)

    Return true iff we are not hidden.  */

-static bool
+bool
 get_current_wm_state (struct frame *f,
                       Window window,
                       int *size_state,