fix: remove XGrabKeyboard from XRecord path — it blocks event delivery

XGrabKeyboard on the same display as XRecord breaks event delivery.
XRecord captures events globally without any grab needed.
Also: use XPending() before select() to check Xlib internal buffer,
and add XFlush before XRecordProcessReplies after select().

daemon/src/main.rs

@@ -577,8 +577,9 @@ fn main() -> Result<(), Box<dyn std::error::Error>> {
     #[cfg(feature = "x11")]
     if display != display::DisplayServer::Wayland {
         if let Some(mut capture) = X11Capture::new() {
-            if capture.grab_keyboard() {
+            // XRecord captures events globally — no grab needed for capture.
-                log_info("[vietc] X11 keyboard grabbed — using X11 capture/injection");
+            // XGrabKeyboard on the same display as XRecord breaks event delivery.
+            log_info("[vietc] X11 XRecord capture active — using X11 capture/injection");
             return run_with_x11(
                 capture,
                 &mut daemon,
@@ -587,9 +588,6 @@ fn main() -> Result<(), Box<dyn std::error::Error>> {
                 status_changed,
                 engine_enabled,
             );
-            } else {
-                log_info("[vietc] X11 grab failed, falling back to evdev");
-            }
         } else {
             log_info("[vietc] X11 not available, falling back to evdev");
         }
@@ -710,6 +708,8 @@ fn run_with_x11(
     // press+release immediately, breaking held-key combos (Ctrl+C, Alt+Tab…).
     let mut pressed_keys: HashSet<u32> = HashSet::new();
 
+    eprintln!("[vietc] X11 event loop starting");
+
     loop {
         if status_changed.load(Ordering::SeqCst) {
             daemon.sync_status_file();
@@ -747,8 +747,13 @@ fn run_with_x11(
         let got_data = capture.wait_for_event(100);
         let evt = capture.next_event();
         if evt.is_none() {
+            static mut LOOP_COUNT: u64 = 0;
+            unsafe { LOOP_COUNT += 1; }
             if got_data {
-                eprintln!("[vietc] DEBUG: select said data but no event in queue");
+                eprintln!("[vietc] DEBUG: select said data but no event in queue (loop={})", unsafe { LOOP_COUNT });
+            }
+            if unsafe { LOOP_COUNT } <= 3 || unsafe { LOOP_COUNT } % 50 == 0 {
+                eprintln!("[vietc] DEBUG: no event, grabbed={}, got_data={}", capture.is_grabbed(), got_data);
             }
             if !capture.is_grabbed() {
                 eprintln!("[vietc] Keyboard grab lost — re-grabbing");

protocol/src/x11_capture.rs

@@ -35,6 +35,7 @@ struct X11Lib {
     x_utf8_lookup_string: Option<unsafe extern "C" fn(*mut XKeyEvent, *mut c_char, c_int, *mut KeySym, *mut c_int) -> c_int>,
     x_flush: unsafe extern "C" fn(*mut Display) -> c_int,
     x_connection_number: unsafe extern "C" fn(*mut Display) -> c_int,
+    x_pending: unsafe extern "C" fn(*mut Display) -> c_int,
     // XRecord
     x_record_query_version: unsafe extern "C" fn(*mut Display, *mut c_int, *mut c_int) -> i32,
     x_record_alloc_range: unsafe extern "C" fn() -> *mut XRecordRange,
@@ -153,6 +154,7 @@ impl X11Lib {
             };
             let x_flush = sym!("XFlush");
             let x_connection_number = sym!("XConnectionNumber");
+            let x_pending = sym!("XPending");
 
             if xtst_handle.is_null() {
                 return Err("Failed to load libXtst.so.6 — install libxtst6".into());
@@ -184,6 +186,7 @@ impl X11Lib {
                 x_utf8_lookup_string,
                 x_flush,
                 x_connection_number,
+                x_pending,
                 x_record_query_version,
                 x_record_alloc_range,
                 x_record_create_context,
@@ -416,11 +419,21 @@ impl X11Capture {
         self.grabbed
     }
 
-    /// Wait for XRecord data to arrive on the X11 connection fd, with timeout.
+    /// Wait for XRecord data to arrive, with timeout.
+    /// Uses XPending() first (checks Xlib internal buffer), then select() on fd.
     pub fn wait_for_event(&mut self, timeout_ms: u64) -> bool {
         unsafe {
             (self.lib.x_flush)(self.display);
 
+            // First check: XPending reads from Xlib's internal buffer.
+            // XRecord data may already be buffered there by a previous read.
+            let pending = (self.lib.x_pending)(self.display);
+            if pending > 0 {
+                (self.lib.x_record_process_replies)(self.display);
+                return true;
+            }
+
+            // Second check: select() on the X11 socket fd
             let fd = (self.lib.x_connection_number)(self.display);
             let mut readfds: FdSet = std::mem::zeroed();
             fd_zero(&mut readfds);
@@ -431,7 +444,8 @@ impl X11Capture {
             };
             let n = select(fd + 1, &mut readfds, std::ptr::null_mut(), std::ptr::null_mut(), &mut timeout);
             if n > 0 && fd_isset(fd, &readfds) {
-                // Process XRecord replies — this fires the callback
+                // Flush to move data from socket into Xlib buffer
+                (self.lib.x_flush)(self.display);
                 (self.lib.x_record_process_replies)(self.display);
                 true
             } else {
@@ -470,10 +484,14 @@ impl X11Capture {
     where
         F: FnOnce() -> T,
     {
+        if self.grabbed {
             self.ungrab_keyboard();
             let result = f();
             self.grab_keyboard();
             result
+        } else {
+            f()
+        }
     }
 
     pub fn lookup_keycode(&self, keycode: u32, state: c_int) -> Option<char> {