diff --git a/packages/coding-agent/src/core/session-manager.ts b/packages/coding-agent/src/core/session-manager.ts
index ef319371..5d6b6c90 100644
--- a/packages/coding-agent/src/core/session-manager.ts
+++ b/packages/coding-agent/src/core/session-manager.ts
@@ -789,7 +789,7 @@ export class SessionManager {
 		// Build tree
 		for (const entry of entries) {
 			const node = nodeMap.get(entry.id)!;
-			if (entry.parentId === null) {
+			if (entry.parentId === null || entry.parentId === entry.id) {
 				roots.push(node);
 			} else {
 				const parent = nodeMap.get(entry.parentId);
@@ -803,11 +803,13 @@ export class SessionManager {
 		}
 
 		// Sort children by timestamp (oldest first, newest at bottom)
-		const sortChildren = (node: SessionTreeNode): void => {
+		// Use iterative approach to avoid stack overflow on deep trees
+		const stack: SessionTreeNode[] = [...roots];
+		while (stack.length > 0) {
+			const node = stack.pop()!;
 			node.children.sort((a, b) => new Date(a.entry.timestamp).getTime() - new Date(b.entry.timestamp).getTime());
-			node.children.forEach(sortChildren);
-		};
-		roots.forEach(sortChildren);
+			stack.push(...node.children);
+		}
 
 		return roots;
 	}
diff --git a/packages/coding-agent/src/modes/interactive/interactive-mode.ts b/packages/coding-agent/src/modes/interactive/interactive-mode.ts
index 70185bc0..b7b4853f 100644
--- a/packages/coding-agent/src/modes/interactive/interactive-mode.ts
+++ b/packages/coding-agent/src/modes/interactive/interactive-mode.ts
@@ -621,6 +621,9 @@ export class InteractiveMode {
 		this.editor.onShiftTab = () => this.cycleThinkingLevel();
 		this.editor.onCtrlP = () => this.cycleModel("forward");
 		this.editor.onShiftCtrlP = () => this.cycleModel("backward");
+
+		// Global debug handler on TUI (works regardless of focus)
+		this.ui.onDebug = () => this.handleDebugCommand();
 		this.editor.onCtrlL = () => this.showModelSelector();
 		this.editor.onCtrlO = () => this.toggleToolOutputExpansion();
 		this.editor.onCtrlT = () => this.toggleThinkingBlockVisibility();
@@ -1645,7 +1648,7 @@ export class InteractiveMode {
 					this.ui.requestRender();
 				},
 			);
-			return { component: selector, focus: selector.getTreeList() };
+			return { component: selector, focus: selector };
 		});
 	}
 
diff --git a/packages/tui/src/index.ts b/packages/tui/src/index.ts
index 71f0eca3..2c741eb8 100644
--- a/packages/tui/src/index.ts
+++ b/packages/tui/src/index.ts
@@ -50,6 +50,7 @@ export {
 	isEnter,
 	isEscape,
 	isHome,
+	isShiftCtrlD,
 	isShiftCtrlP,
 	isShiftEnter,
 	isShiftTab,
diff --git a/packages/tui/src/keys.ts b/packages/tui/src/keys.ts
index edd2c06d..12965fec 100644
--- a/packages/tui/src/keys.ts
+++ b/packages/tui/src/keys.ts
@@ -320,6 +320,14 @@ export function isShiftCtrlP(data: string): boolean {
 	return matchesKittySequence(data, CODEPOINTS.p, MODIFIERS.shift + MODIFIERS.ctrl);
 }
 
+/**
+ * Check if input matches Shift+Ctrl+D (Kitty protocol only, for debug).
+ * Ignores lock key bits.
+ */
+export function isShiftCtrlD(data: string): boolean {
+	return matchesKittySequence(data, CODEPOINTS.d, MODIFIERS.shift + MODIFIERS.ctrl);
+}
+
 /**
  * Check if input matches Ctrl+T (raw byte or Kitty protocol).
  * Ignores lock key bits.
diff --git a/packages/tui/src/tui.ts b/packages/tui/src/tui.ts
index 1baf5e4d..583f099e 100644
--- a/packages/tui/src/tui.ts
+++ b/packages/tui/src/tui.ts
@@ -5,6 +5,7 @@
 import * as fs from "node:fs";
 import * as os from "node:os";
 import * as path from "node:path";
+import { isShiftCtrlD } from "./keys.js";
 import type { Terminal } from "./terminal.js";
 import { getCapabilities, setCellDimensions } from "./terminal-image.js";
 import { visibleWidth } from "./utils.js";
@@ -78,6 +79,9 @@ export class TUI extends Container {
 	private previousLines: string[] = [];
 	private previousWidth = 0;
 	private focusedComponent: Component | null = null;
+
+	/** Global callback for debug key (Shift+Ctrl+D). Called before input is forwarded to focused component. */
+	public onDebug?: () => void;
 	private renderRequested = false;
 	private cursorRow = 0; // Track where cursor is (0-indexed, relative to our first line)
 	private inputBuffer = ""; // Buffer for parsing terminal responses
@@ -141,6 +145,12 @@ export class TUI extends Container {
 			data = filtered;
 		}
 
+		// Global debug key handler (Shift+Ctrl+D)
+		if (isShiftCtrlD(data) && this.onDebug) {
+			this.onDebug();
+			return;
+		}
+
 		// Pass input to focused component (including Ctrl+C)
 		// The focused component can decide how to handle Ctrl+C
 		if (this.focusedComponent?.handleInput) {