From f4552cd60e1d46ac7fbbe8f956fa7190f73aedee Mon Sep 17 00:00:00 2001
From: Yuto Nishida <yuto@berkeley.edu>
Date: Sat, 10 Oct 2026 14:30:12 -0700
Subject: [PATCH] papyrus: preserve Shift+Enter for Codex sessions

---
 .../papyrus/client/src/components/Sidebar.tsx |  1 +
 .../client/src/components/Terminal.tsx        | 23 ++++++++++++++++++-
 2 files changed, 23 insertions(+), 1 deletion(-)

diff --git a/experimental/papyrus/client/src/components/Sidebar.tsx b/experimental/papyrus/client/src/components/Sidebar.tsx
index 5db2792..68e5c50 100644
--- a/experimental/papyrus/client/src/components/Sidebar.tsx
+++ b/experimental/papyrus/client/src/components/Sidebar.tsx
@@ -771,6 +771,7 @@ export function Sidebar() {
                   <Terminal
                     key={activeTab.sessionId}
                     sessionId={activeTab.sessionId}
+                    kind={activeTab.kind}
                     color={displayColor}
                   />
                 </div>
diff --git a/experimental/papyrus/client/src/components/Terminal.tsx b/experimental/papyrus/client/src/components/Terminal.tsx
index fed598a..67563b7 100644
--- a/experimental/papyrus/client/src/components/Terminal.tsx
+++ b/experimental/papyrus/client/src/components/Terminal.tsx
@@ -7,10 +7,11 @@ import { fontStack, fontSizeFor } from "../settings";
 
 interface TerminalProps {
   sessionId: string;
+  kind: string;
   color: string;
 }
 
-export function Terminal({ sessionId, color }: TerminalProps) {
+export function Terminal({ sessionId, kind, color }: TerminalProps) {
   const terminalRef = useRef<HTMLDivElement>(null);
   const backendRef = useRef<TerminalBackend | null>(null);
   const wsRef = useRef<WebSocket | null>(null);
@@ -245,6 +246,26 @@ export function Terminal({ sessionId, color }: TerminalProps) {
     return () => el.removeEventListener("paste", onPaste, { capture: true });
   }, []);
 
+  useEffect(() => {
+    if (kind !== "codex") return;
+    const el = terminalRef.current;
+    if (!el) return;
+    const onKeyDown = (e: KeyboardEvent) => {
+      if (
+        e.key !== "Enter" || !e.shiftKey || e.ctrlKey || e.altKey || e.metaKey || e.isComposing
+      ) return;
+      // Send the modified key before either emulator turns Shift+Enter into plain Enter.
+      e.preventDefault();
+      e.stopImmediatePropagation();
+      const ws = wsRef.current;
+      if (ws?.readyState === WebSocket.OPEN) {
+        ws.send(JSON.stringify({ type: "input", data: "\x1b[13;2u" }));
+      }
+    };
+    el.addEventListener("keydown", onKeyDown, { capture: true });
+    return () => el.removeEventListener("keydown", onKeyDown, { capture: true });
+  }, [kind]);
+
   return (
     <div
       ref={terminalRef}
-- 
2.51.2