diff --git a/packages/tui/src/components-new/editor.ts b/packages/tui/src/components-new/editor.ts
index f5f6a429..0474363b 100644
--- a/packages/tui/src/components-new/editor.ts
+++ b/packages/tui/src/components-new/editor.ts
@@ -265,10 +265,11 @@ export class Editor implements Component {
 			// Get text and substitute paste markers with actual content
 			let result = this.state.lines.join("\n").trim();
 
-			// Replace all [paste #N] markers with actual paste content
+			// Replace all [paste #N +xxx lines] markers with actual paste content
 			for (const [pasteId, pasteContent] of this.pastes) {
-				const marker = `[paste #${pasteId}]`;
-				result = result.replace(marker, pasteContent);
+				// Match both old format [paste #N] and new format [paste #N +xxx lines]
+				const markerRegex = new RegExp(`\\[paste #${pasteId}( \\+\\d+ lines)?\\]`, "g");
+				result = result.replace(markerRegex, pasteContent);
 			}
 
 			// Reset editor and clear pastes
@@ -472,8 +473,8 @@ export class Editor implements Component {
 			const pasteId = this.pasteCounter;
 			this.pastes.set(pasteId, filteredText);
 
-			// Insert marker like "[paste #1]"
-			const marker = `[paste #${pasteId}]`;
+			// Insert marker like "[paste #1 +123 lines]"
+			const marker = `[paste #${pasteId} +${pastedLines.length} lines]`;
 			for (const char of marker) {
 				this.insertCharacter(char);
 			}
diff --git a/packages/tui/test/chat-debug.ts b/packages/tui/test/chat-debug.ts
new file mode 100644
index 00000000..f1352477
--- /dev/null
+++ b/packages/tui/test/chat-debug.ts
@@ -0,0 +1,48 @@
+/**
+ * Debug version of chat-simple with logging
+ */
+
+import fs from "fs";
+import { ProcessTerminal } from "../src/terminal.js";
+import { Input, Text, TUI } from "../src/tui-new.js";
+
+// Clear debug log
+fs.writeFileSync("debug.log", "");
+
+function log(msg: string) {
+	fs.appendFileSync("debug.log", msg + "\n");
+}
+
+// Create terminal
+const terminal = new ProcessTerminal();
+
+// Wrap terminal methods to log
+const originalWrite = terminal.write.bind(terminal);
+const originalMoveBy = terminal.moveBy.bind(terminal);
+
+terminal.write = (data: string) => {
+	log(`WRITE: ${JSON.stringify(data)}`);
+	originalWrite(data);
+};
+
+terminal.moveBy = (lines: number) => {
+	log(`MOVEBY: ${lines}`);
+	originalMoveBy(lines);
+};
+
+// Create TUI
+const tui = new TUI(terminal);
+
+// Create chat container with some initial messages
+tui.addChild(new Text("Welcome to Simple Chat!"));
+tui.addChild(new Text("Type your messages below. Press Ctrl+C to exit.\n"));
+
+// Create input field
+const input = new Input();
+tui.addChild(input);
+
+// Focus the input
+tui.setFocus(input);
+
+// Start the TUI
+tui.start();