From c4751749d0ba13cb3deaa1c94404f2900899cb7f Mon Sep 17 00:00:00 2001
From: aotian16 <aotian16@gmail.com>
Date: Mon, 6 Jul 2026 10:39:38 +0800
Subject: [PATCH] fix(desktop): guard IME submit against Chromium
 Enter-after-compositionend edge case

On macOS, some Chinese IMEs trigger a Chromium bug where the Enter
keydown event is dispatched *after* compositionend without setting
nativeEvent.isComposing=true.  The existing composingRef + isComposing
guards both miss this window, so pressing Enter to confirm an IME
candidate fires submitDraft() instead.

Fix: introduce recentCompositionRef, set true on compositionend and
cleared after 100ms.  The keydown handler checks this flag as a third
guard alongside composingRef and isComposing, covering all known IME
timing scenarios.
---
 apps/desktop/src/app/chat/composer/index.tsx | 25 +++++++++++++++-----
 1 file changed, 19 insertions(+), 6 deletions(-)

diff --git a/apps/desktop/src/app/chat/composer/index.tsx b/apps/desktop/src/app/chat/composer/index.tsx
index 1f5df46eb2a47..b0ad3996b5342 100644
--- a/apps/desktop/src/app/chat/composer/index.tsx
+++ b/apps/desktop/src/app/chat/composer/index.tsx
@@ -121,6 +121,7 @@ export function ChatBar({
   // engine writes it — an explicit shared handle, not a back-reference.
   const queueEditRef = useRef<QueueEditState | null>(null)
   const composingRef = useRef(false) // true during IME composition (CJK input)
+  const recentCompositionRef = useRef(false) // true briefly after compositionend — catches Enter keydowns that Chromium dispatches without isComposing=true
 
   const { availableThemes, themeName } = useTheme()
   const at = useAtCompletions({ gateway: gateway ?? null, sessionId: sessionId ?? null, cwd: cwd ?? null })
@@ -363,11 +364,14 @@ export function ChatBar({
 
   const handleEditorKeyDown = (event: KeyboardEvent<HTMLDivElement>) => {
     // IME composition: Enter confirms composed text, not a message submission.
-    // We check both composingRef (set by compositionstart/compositionend, robust
-    // across browsers) and nativeEvent.isComposing (Chromium fallback).  Without
-    // this guard, pressing Enter to finalise a Korean/Japanese/Chinese IME
-    // preedit fires submitDraft() and splits the message mid-word.
-    if (composingRef.current || event.nativeEvent.isComposing) {
+    // We check composingRef (set by compositionstart/compositionend, robust
+    // across browsers), nativeEvent.isComposing (Chromium fallback), and
+    // recentCompositionRef (catches Enter keydowns that Chromium dispatches
+    // *after* compositionend without isComposing=true — a known macOS Chinese
+    // IME edge case).  Without this guard, pressing Enter to finalise a
+    // Korean/Japanese/Chinese IME preedit fires submitDraft() and splits the
+    // message mid-word.
+    if (composingRef.current || event.nativeEvent.isComposing || recentCompositionRef.current) {
       return
     }
 
@@ -727,11 +731,20 @@ export function ChatBar({
         onCompositionEnd={event => {
           composingRef.current = false
 
+          // Chromium on macOS sometimes dispatches the Enter keydown event
+          // *after* compositionend, without setting isComposing=true on the
+          // native event.  The brief guard window prevents that Enter from
+          // submitting the draft instead of committing the IME candidate.
+          recentCompositionRef.current = true
+          setTimeout(() => {
+            recentCompositionRef.current = false
+          }, 100)
+
           // The input events fired *during* composition were skipped (they
           // carried uncommitted preedit text), and Chromium does NOT reliably
           // emit a trailing input event after compositionend on Windows IMEs.
           // Without flushing here, committed multi-character IME input (e.g.
-          // Chinese "你好", Japanese, Korean) never reaches composer state, so
+          // Chinese 你好, Japanese, Korean) never reaches composer state, so
           // `hasComposerPayload` stays false and the send button stays hidden
           // until an unrelated edit forces a sync (#39614).
           flushEditorToDraft(event.currentTarget)