diff --git a/packages/opencode/src/cli/cmd/tui/app.tsx b/packages/opencode/src/cli/cmd/tui/app.tsx
index 0d5aefe7bc3..543487b2b79 100644
--- a/packages/opencode/src/cli/cmd/tui/app.tsx
+++ b/packages/opencode/src/cli/cmd/tui/app.tsx
@@ -577,17 +577,11 @@ function App() {
       },
     },
     {
-      title: terminalTitleEnabled() ? "Disable terminal title" : "Enable terminal title",
-      value: "terminal.title.toggle",
-      keybind: "terminal_title_toggle",
+      title: kv.get("sidebar_overlay", true) ? "Disable sidebar overlay" : "Enable sidebar overlay",
+      value: "sidebar_overlay",
       category: "System",
       onSelect: (dialog) => {
-        setTerminalTitleEnabled((prev) => {
-          const next = !prev
-          kv.set("terminal_title_enabled", next)
-          if (!next) renderer.setTerminalTitle("")
-          return next
-        })
+        kv.set("sidebar_overlay", !kv.get("sidebar_overlay", true))
         dialog.clear()
       },
     },
diff --git a/packages/opencode/src/cli/cmd/tui/routes/session/index.tsx b/packages/opencode/src/cli/cmd/tui/routes/session/index.tsx
index 77872eedadd..e7430ea9eca 100644
--- a/packages/opencode/src/cli/cmd/tui/routes/session/index.tsx
+++ b/packages/opencode/src/cli/cmd/tui/routes/session/index.tsx
@@ -149,6 +149,7 @@ export function Session() {
   const [showDetails, setShowDetails] = kv.signal("tool_details_visibility", true)
   const [showAssistantMetadata, setShowAssistantMetadata] = kv.signal("assistant_metadata_visibility", true)
   const [showScrollbar, setShowScrollbar] = kv.signal("scrollbar_visible", false)
+  const [sidebarOverlayEnabled, setSidebarOverlayEnabled] = kv.signal("sidebar_overlay", true)
   const [diffWrapMode] = kv.signal<"word" | "none">("diff_wrap_mode", "word")
   const [animationsEnabled, setAnimationsEnabled] = kv.signal("animations_enabled", true)
 
@@ -159,8 +160,12 @@ export function Session() {
     if (sidebar() === "auto" && wide()) return true
     return false
   })
+  const sidebarOverlay = createMemo(() => {
+    if (!sidebarOverlayEnabled()) return false
+    return sidebarVisible() && !wide()
+  })
   const showTimestamps = createMemo(() => timestamps() === "show")
-  const contentWidth = createMemo(() => dimensions().width - (sidebarVisible() ? 42 : 0) - 4)
+  const contentWidth = createMemo(() => dimensions().width - (sidebarVisible() && !sidebarOverlay() ? 42 : 0) - 4)
 
   const scrollAcceleration = createMemo(() => {
     const tui = sync.data.config.tui
@@ -958,7 +963,7 @@ export function Session() {
       <box flexDirection="row">
         <box flexGrow={1} paddingBottom={1} paddingTop={1} paddingLeft={2} paddingRight={2} gap={1}>
           <Show when={session()}>
-            <Show when={!sidebarVisible() || !wide()}>
+            <Show when={!sidebarVisible() || sidebarOverlay()}>
               <Header />
             </Show>
             <scrollbox
@@ -1107,10 +1112,10 @@ export function Session() {
         </box>
         <Show when={sidebarVisible()}>
           <Switch>
-            <Match when={wide()}>
+            <Match when={!sidebarOverlay()}>
               <Sidebar sessionID={route.sessionID} />
             </Match>
-            <Match when={!wide()}>
+            <Match when={sidebarOverlay()}>
               <box
                 position="absolute"
                 top={0}
diff --git a/packages/opencode/src/cli/cmd/tui/routes/session/sidebar.tsx b/packages/opencode/src/cli/cmd/tui/routes/session/sidebar.tsx
index 4ffe91558ed..09ce916b66f 100644
--- a/packages/opencode/src/cli/cmd/tui/routes/session/sidebar.tsx
+++ b/packages/opencode/src/cli/cmd/tui/routes/session/sidebar.tsx
@@ -12,7 +12,7 @@ import { useDirectory } from "../../context/directory"
 import { useKV } from "../../context/kv"
 import { TodoItem } from "../../component/todo-item"
 
-export function Sidebar(props: { sessionID: string; overlay?: boolean }) {
+export function Sidebar(props: { sessionID: string }) {
   const sync = useSync()
   const { theme } = useTheme()
   const session = createMemo(() => sync.session.get(props.sessionID)!)
@@ -78,7 +78,7 @@ export function Sidebar(props: { sessionID: string; overlay?: boolean }) {
         paddingBottom={1}
         paddingLeft={2}
         paddingRight={2}
-        position={props.overlay ? "absolute" : "relative"}
+        position="relative"
       >
         <scrollbox flexGrow={1}>
           <box flexShrink={0} gap={1} paddingRight={1}>
diff --git a/packages/opencode/src/config/config.ts b/packages/opencode/src/config/config.ts
index a231a530072..12ffe418301 100644
--- a/packages/opencode/src/config/config.ts
+++ b/packages/opencode/src/config/config.ts
@@ -810,6 +810,7 @@ export namespace Config {
         .default("<leader>h")
         .describe("Toggle code block concealment in messages"),
       tool_details: z.string().optional().default("none").describe("Toggle tool details visibility"),
+      sidebar_overlay_toggle: z.string().optional().default("none").describe("Toggle sidebar overlay mode"),
       model_list: z.string().optional().default("<leader>m").describe("List available models"),
       model_cycle_recent: z.string().optional().default("f2").describe("Next recently used model"),
       model_cycle_recent_reverse: z.string().optional().default("shift+f2").describe("Previous recently used model"),