fix error

src-tauri/src/lib.rs

@@ -8,6 +8,15 @@ use x11mod::{
 
 #[cfg_attr(mobile, tauri::mobile_entry_point)]
 pub fn run() {
+    // X11 reparenting requires our own window to be an X11 window. On Wayland
+    // sessions, GTK defaults to the Wayland backend and embedding is impossible.
+    // Force the X11 backend (via XWayland on Wayland sessions) so we always get
+    // an X11 toplevel we can reparent into.
+    #[cfg(target_os = "linux")]
+    {
+        std::env::set_var("GDK_BACKEND", "x11");
+    }
+
     tauri::Builder::default()
         .manage(PtyState::default())
         .manage(X11State::new())