diff --git a/README.ja.md b/README.ja.md
index ac7950f7eb0..6491f60020f 100644
--- a/README.ja.md
+++ b/README.ja.md
@@ -70,6 +70,7 @@ VS Codeのフォーク。本家にはないUI/UX改善を追加した(してい
 | `coderm.quickOpen.includeTerminals`              | `boolean`  | `true`                                           | Quick Openにターミナルエディタを含める             |
 | `coderm.updateDownloadProgress.enabled`          | `boolean`  | `true`                                           | アップデートダウンロード時に進捗通知を表示         |
 | `coderm.terminal.closeEmptyPaneOnKill`           | `boolean`  | `true`                                           | ターミナルkill時に空ペインを閉じてフォーカス復帰   |
+| `coderm.titleBar.hideMoreActions`                | `boolean`  | `true`                                           | タイトルバー右端の「More Actions (`...`)」オーバーフローボタンを非表示 |
 
 ---
 
diff --git a/README.md b/README.md
index f143d937e03..f6d6b1252f6 100644
--- a/README.md
+++ b/README.md
@@ -70,6 +70,7 @@ Settings unique to Coderm that are not available in upstream VS Code.
 | `coderm.quickOpen.includeTerminals`              | `boolean`  | `true`                                           | Include terminal editors in Quick Open              |
 | `coderm.updateDownloadProgress.enabled`          | `boolean`  | `true`                                           | Show progress notification during update download   |
 | `coderm.terminal.closeEmptyPaneOnKill`           | `boolean`  | `true`                                           | Close empty pane and restore focus on terminal kill |
+| `coderm.titleBar.hideMoreActions`                | `boolean`  | `true`                                           | Hide the trailing "More Actions" overflow button (`...`) in the title bar |
 
 ---
 
diff --git a/src/vs/workbench/contrib/coderm/browser/coderm.contribution.ts b/src/vs/workbench/contrib/coderm/browser/coderm.contribution.ts
index b0d04869303..b051005ba1a 100644
--- a/src/vs/workbench/contrib/coderm/browser/coderm.contribution.ts
+++ b/src/vs/workbench/contrib/coderm/browser/coderm.contribution.ts
@@ -17,6 +17,7 @@ import './devTitlePrefix.js';
 import './eagerExtensions.js';
 import './editorGroupIndex.js';
 import './gitWorktreeDefaults.js';
+import './hideTitleBarMoreActions.js';
 import './preventNewGroupOnFocus.js';
 import './quickOpenIncludeTerminals.js';
 import './resizePaneActions.js';
diff --git a/src/vs/workbench/contrib/coderm/browser/hideTitleBarMoreActions.ts b/src/vs/workbench/contrib/coderm/browser/hideTitleBarMoreActions.ts
new file mode 100644
index 00000000000..75161aaa04f
--- /dev/null
+++ b/src/vs/workbench/contrib/coderm/browser/hideTitleBarMoreActions.ts
@@ -0,0 +1,101 @@
+/*---------------------------------------------------------------------------------------------
+ *  Copyright (c) Microsoft Corporation. All rights reserved.
+ *  Licensed under the MIT License. See License.txt in the project root for license information.
+ *--------------------------------------------------------------------------------------------*/
+
+/**
+ * Hides the title bar's trailing "More Actions" overflow button (`...`). Driven
+ * via a body class + CSS because `WorkbenchToolBar.setActions` repopulates the
+ * overflow bucket from `primary` whenever items exceed `maxItems`, so dropping
+ * the `secondary` argument from the call site has no effect on the button.
+ */
+
+import { mainWindow } from '../../../../base/browser/window.js';
+import { createStyleSheet } from '../../../../base/browser/domStylesheets.js';
+import { Disposable } from '../../../../base/common/lifecycle.js';
+import { IConfigurationService } from '../../../../platform/configuration/common/configuration.js';
+import { ConfigurationScope, Extensions as ConfigurationExtensions, IConfigurationRegistry } from '../../../../platform/configuration/common/configurationRegistry.js';
+import { Registry } from '../../../../platform/registry/common/platform.js';
+import { localize } from '../../../../nls.js';
+import { IWorkbenchContribution, WorkbenchPhase, registerWorkbenchContribution2 } from '../../../common/contributions.js';
+
+export const CodermHideTitleBarMoreActionsSetting = 'coderm.titleBar.hideMoreActions';
+
+const BODY_CLASS = 'coderm-hide-title-bar-more-actions';
+
+// #region Configuration
+
+// Constraint: APPLICATION scope is intentional because hiding the title bar
+// overflow is a host-level visual choice; per-workspace overrides would
+// fragment the title bar UX across windows (sibling pattern: cursorAutoHide.ts).
+Registry.as<IConfigurationRegistry>(ConfigurationExtensions.Configuration)
+	.registerConfiguration({
+		id: 'coderm.titleBar',
+		// Note: order=106 reserves a stable slot after existing Coderm settings
+		// (activePaneBorder=100, cursorAutoHide=101, ...) so the Settings UI
+		// renders this section predictably relative to siblings.
+		order: 106,
+		title: localize('codermConfigurationTitle', "Coderm"),
+		type: 'object',
+		properties: {
+			[CodermHideTitleBarMoreActionsSetting]: {
+				type: 'boolean',
+				default: true,
+				scope: ConfigurationScope.APPLICATION,
+				description: localize('coderm.titleBar.hideMoreActions', "Controls whether the trailing \"More Actions\" overflow button (`...`) is hidden in the title bar. When enabled, secondary title bar actions (e.g. items contributed by extensions such as Copilot Chat) are not surfaced via the overflow menu."),
+			},
+		},
+	});
+
+// #endregion
+
+// #region Stylesheet
+
+createStyleSheet(undefined, sheet => {
+	// Why: `:has(.codicon-toolbar-more)` targets only the overflow `...` action
+	// item, never other title bar actions, because WorkbenchToolBar reuses the
+	// generic `.action-item` class for every entry (see file-level JSDoc for
+	// why a CSS hook is required instead of removing the action source).
+	// Constraint: `!important` is required to win specificity over the host's
+	// inline `flex: 1` / `display: flex` rules on `.action-item`.
+	sheet.textContent = `
+		/* Coderm: hide the "More Actions" overflow button in the title bar's action toolbar. */
+		.${BODY_CLASS} .titlebar-right .action-toolbar-container
+			.monaco-action-bar .action-item:has(.codicon-toolbar-more) {
+			display: none !important;
+		}
+	`;
+});
+
+// #endregion
+
+// #region Controller
+
+class HideTitleBarMoreActionsController extends Disposable implements IWorkbenchContribution {
+
+	static readonly ID = 'workbench.contrib.coderm.hideTitleBarMoreActions';
+
+	constructor(@IConfigurationService private readonly configurationService: IConfigurationService) {
+		super();
+
+		this._store.add(configurationService.onDidChangeConfiguration(e => {
+			if (e.affectsConfiguration(CodermHideTitleBarMoreActionsSetting)) {
+				this._apply();
+			}
+		}));
+
+		this._apply();
+	}
+
+	private _apply(): void {
+		const enabled = this.configurationService.getValue<boolean>(CodermHideTitleBarMoreActionsSetting) ?? true;
+		mainWindow.document.body.classList.toggle(BODY_CLASS, enabled);
+	}
+}
+
+// Why: AfterRestored (not BlockBeforeRestored) so the title bar toolbar DOM is
+// present when _apply() runs the first time; earlier phases would race the
+// layout restore and the body class could be applied before the toolbar exists.
+registerWorkbenchContribution2(HideTitleBarMoreActionsController.ID, HideTitleBarMoreActionsController, WorkbenchPhase.AfterRestored);
+
+// #endregion