Index: uspace/lib/ui/src/window.c
===================================================================
--- uspace/lib/ui/src/window.c	(revision 0d00e53ee0e707747c5d846467b5eddfa7a0e101)
+++ uspace/lib/ui/src/window.c	(revision fa3ed5b2ad5250dbbe32d35a1db4cf866f983ba6)
@@ -1,4 +1,4 @@
 /*
- * Copyright (c) 2024 Jiri Svoboda
+ * Copyright (c) 2025 Jiri Svoboda
  * All rights reserved.
  *
@@ -978,7 +978,7 @@
 	ui_t *ui = window->ui;
 
-	ui_lock(ui);
+	fibril_mutex_lock(&ui->lock);
 	ui_window_send_close(window);
-	ui_unlock(ui);
+	fibril_mutex_unlock(&ui->lock);
 }
 
@@ -989,5 +989,5 @@
 	ui_t *ui = window->ui;
 
-	ui_lock(ui);
+	fibril_mutex_lock(&ui->lock);
 	(void)nfocus;
 
@@ -998,5 +998,5 @@
 
 	ui_window_send_focus(window, nfocus);
-	ui_unlock(ui);
+	fibril_mutex_unlock(&ui->lock);
 }
 
@@ -1007,7 +1007,7 @@
 	ui_t *ui = window->ui;
 
-	ui_lock(ui);
+	fibril_mutex_lock(&ui->lock);
 	ui_window_send_kbd(window, kbd_event);
-	ui_unlock(ui);
+	fibril_mutex_unlock(&ui->lock);
 }
 
@@ -1023,14 +1023,14 @@
 		return;
 
-	ui_lock(ui);
+	fibril_mutex_lock(&ui->lock);
 
 	claim = ui_wdecor_pos_event(window->wdecor, event);
 	if (claim == ui_claimed) {
-		ui_unlock(ui);
+		fibril_mutex_unlock(&ui->lock);
 		return;
 	}
 
 	ui_window_send_pos(window, event);
-	ui_unlock(ui);
+	fibril_mutex_unlock(&ui->lock);
 }
 
@@ -1048,8 +1048,8 @@
 		return;
 
-	ui_lock(ui);
+	fibril_mutex_lock(&ui->lock);
 	(void) ui_window_resize(window, rect);
 	ui_window_send_resize(window);
-	ui_unlock(ui);
+	fibril_mutex_unlock(&ui->lock);
 }
 
@@ -1060,5 +1060,5 @@
 	ui_t *ui = window->ui;
 
-	ui_lock(ui);
+	fibril_mutex_lock(&ui->lock);
 
 	if (window->wdecor != NULL && nfocus == 0) {
@@ -1068,5 +1068,5 @@
 
 	ui_window_send_unfocus(window, nfocus);
-	ui_unlock(ui);
+	fibril_mutex_unlock(&ui->lock);
 }