diff --git a/tauri/src-tauri/Cargo.lock b/tauri/src-tauri/Cargo.lock
index 779f098c0..bd71ea788 100644
--- a/tauri/src-tauri/Cargo.lock
+++ b/tauri/src-tauri/Cargo.lock
@@ -84,6 +84,137 @@ version = "0.7.6"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "7c02d123df017efcdfbd739ef81735b36c5ba83ec3c59c80a9d7ecc718f92e50"
 
+[[package]]
+name = "async-broadcast"
+version = "0.7.2"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "435a87a52755b8f27fcf321ac4f04b2802e337c8c4872923137471ec39c37532"
+dependencies = [
+ "event-listener",
+ "event-listener-strategy",
+ "futures-core",
+ "pin-project-lite",
+]
+
+[[package]]
+name = "async-channel"
+version = "2.5.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "924ed96dd52d1b75e9c1a3e6275715fd320f5f9439fb5a4a11fa51f4221158d2"
+dependencies = [
+ "concurrent-queue",
+ "event-listener-strategy",
+ "futures-core",
+ "pin-project-lite",
+]
+
+[[package]]
+name = "async-executor"
+version = "1.14.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "c96bf972d85afc50bf5ab8fe2d54d1586b4e0b46c97c50a0c9e71e2f7bcd812a"
+dependencies = [
+ "async-task",
+ "concurrent-queue",
+ "fastrand",
+ "futures-lite",
+ "pin-project-lite",
+ "slab",
+]
+
+[[package]]
+name = "async-io"
+version = "2.6.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "456b8a8feb6f42d237746d4b3e9a178494627745c3c56c6ea55d92ba50d026fc"
+dependencies = [
+ "autocfg",
+ "cfg-if",
+ "concurrent-queue",
+ "futures-io",
+ "futures-lite",
+ "parking",
+ "polling",
+ "rustix",
+ "slab",
+ "windows-sys 0.61.2",
+]
+
+[[package]]
+name = "async-lock"
+version = "3.4.2"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "290f7f2596bd5b78a9fec8088ccd89180d7f9f55b94b0576823bbbdc72ee8311"
+dependencies = [
+ "event-listener",
+ "event-listener-strategy",
+ "pin-project-lite",
+]
+
+[[package]]
+name = "async-process"
+version = "2.5.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "fc50921ec0055cdd8a16de48773bfeec5c972598674347252c0399676be7da75"
+dependencies = [
+ "async-channel",
+ "async-io",
+ "async-lock",
+ "async-signal",
+ "async-task",
+ "blocking",
+ "cfg-if",
+ "event-listener",
+ "futures-lite",
+ "rustix",
+]
+
+[[package]]
+name = "async-recursion"
+version = "1.1.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "3b43422f69d8ff38f95f1b2bb76517c91589a924d1559a0e935d7c8ce0274c11"
+dependencies = [
+ "proc-macro2",
+ "quote",
+ "syn 2.0.114",
+]
+
+[[package]]
+name = "async-signal"
+version = "0.2.14"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "52b5aaafa020cf5053a01f2a60e8ff5dccf550f0f77ec54a4e47285ac2bab485"
+dependencies = [
+ "async-io",
+ "async-lock",
+ "atomic-waker",
+ "cfg-if",
+ "futures-core",
+ "futures-io",
+ "rustix",
+ "signal-hook-registry",
+ "slab",
+ "windows-sys 0.61.2",
+]
+
+[[package]]
+name = "async-task"
+version = "4.7.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "8b75356056920673b02621b35afd0f7dda9306d03c79a30f5c56c44cf256e3de"
+
+[[package]]
+name = "async-trait"
+version = "0.1.92"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "82f6aeea286b8eb4dd3431a1be1b59d290ace00f5bfd8e2a159bc2a05e2c1667"
+dependencies = [
+ "proc-macro2",
+ "quote",
+ "syn 3.0.3",
+]
+
 [[package]]
 name = "atk"
 version = "0.18.2"
@@ -194,6 +325,19 @@ dependencies = [
  "objc2",
 ]
 
+[[package]]
+name = "blocking"
+version = "1.6.2"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "e83f8d02be6967315521be875afa792a316e28d57b5a2d401897e2a7921b7f21"
+dependencies = [
+ "async-channel",
+ "async-task",
+ "futures-io",
+ "futures-lite",
+ "piper",
+]
+
 [[package]]
 name = "brotli"
 version = "8.0.2"
@@ -402,6 +546,15 @@ dependencies = [
  "memchr",
 ]
 
+[[package]]
+name = "concurrent-queue"
+version = "2.5.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "4ca0197aee26d1ae37445ee532fefce43251d24cc7c166799f4d46817f1d3973"
+dependencies = [
+ "crossbeam-utils",
+]
+
 [[package]]
 name = "convert_case"
 version = "0.4.0"
@@ -820,6 +973,33 @@ dependencies = [
  "cfg-if",
 ]
 
+[[package]]
+name = "endi"
+version = "1.1.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "66b7e2430c6dff6a955451e2cfc438f09cea1965a9d6f87f7e3b90decc014099"
+
+[[package]]
+name = "enumflags2"
+version = "0.7.12"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "1027f7680c853e056ebcec683615fb6fbbc07dbaa13b4d5d9442b146ded4ecef"
+dependencies = [
+ "enumflags2_derive",
+ "serde",
+]
+
+[[package]]
+name = "enumflags2_derive"
+version = "0.7.12"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "67c78a4d8fdf9953a5c9d458f9efe940fd97a0cab0941c075a813ac594733827"
+dependencies = [
+ "proc-macro2",
+ "quote",
+ "syn 2.0.114",
+]
+
 [[package]]
 name = "equivalent"
 version = "1.0.2"
@@ -859,6 +1039,26 @@ dependencies = [
  "nix",
 ]
 
+[[package]]
+name = "event-listener"
+version = "5.4.2"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "5a23add41df1562121a9393cb065eab5146a1242410f23a644851e90cfd669d2"
+dependencies = [
+ "parking",
+ "pin-project-lite",
+]
+
+[[package]]
+name = "event-listener-strategy"
+version = "0.5.4"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "8be9f3dfaaffdae2972880079a491a1a8bb7cbed0b8dd7a347f668b4150a3b93"
+dependencies = [
+ "event-listener",
+ "pin-project-lite",
+]
+
 [[package]]
 name = "extended"
 version = "0.1.0"
@@ -1023,6 +1223,19 @@ version = "0.3.31"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "9e5c1b78ca4aae1ac06c48a526a655760685149f0d465d21f37abfe57ce075c6"
 
+[[package]]
+name = "futures-lite"
+version = "2.6.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "f78e10609fe0e0b3f4157ffab1876319b5b0db102a2c60dc4626306dc46b44ad"
+dependencies = [
+ "fastrand",
+ "futures-core",
+ "futures-io",
+ "parking",
+ "pin-project-lite",
+]
+
 [[package]]
 name = "futures-macro"
 version = "0.3.31"
@@ -1410,6 +1623,12 @@ version = "0.5.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "2304e00983f87ffb38b55b444b5e3b60a884b5d30c0fca7d82fe33449bbe55ea"
 
+[[package]]
+name = "hermit-abi"
+version = "0.5.2"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "fc0fef456e4baa96da950455cd02c081ca953b141298e41db3fc7e36b1da849c"
+
 [[package]]
 name = "hex"
 version = "0.4.3"
@@ -2621,6 +2840,16 @@ version = "0.2.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "04744f49eae99ab78e0d5c0b603ab218f515ea8cfe5a456d7629ad883a3b6e7d"
 
+[[package]]
+name = "ordered-stream"
+version = "0.2.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "9aa2b01e1d916879f73a53d01d1d6cee68adbb31d6d9177a8cfce093cced1d50"
+dependencies = [
+ "futures-core",
+ "pin-project-lite",
+]
+
 [[package]]
 name = "os_pipe"
 version = "1.2.3"
@@ -2670,6 +2899,12 @@ dependencies = [
  "system-deps",
 ]
 
+[[package]]
+name = "parking"
+version = "2.2.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "f38d5652c16fde515bb1ecef450ab0f6a219d619a7274976324d5e377f7dceba"
+
 [[package]]
 name = "parking_lot"
 version = "0.12.5"
@@ -2851,6 +3086,17 @@ version = "0.1.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "8b870d8c151b6f2fb93e84a13146138f05d02ed11c7e7c54f8826aaaf7c9f184"
 
+[[package]]
+name = "piper"
+version = "0.2.5"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "c835479a4443ded371d6c535cbfd8d31ad92c5d23ae9770a61bc155e4992a3c1"
+dependencies = [
+ "atomic-waker",
+ "fastrand",
+ "futures-io",
+]
+
 [[package]]
 name = "pkg-config"
 version = "0.3.32"
@@ -2883,6 +3129,20 @@ dependencies = [
  "miniz_oxide",
 ]
 
+[[package]]
+name = "polling"
+version = "3.11.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "5d0e4f59085d47d8241c88ead0f274e8a0cb551f3625263c05eb8dd897c34218"
+dependencies = [
+ "cfg-if",
+ "concurrent-queue",
+ "hermit-abi",
+ "pin-project-lite",
+ "rustix",
+ "windows-sys 0.61.2",
+]
+
 [[package]]
 name = "potential_utf"
 version = "0.1.4"
@@ -4141,6 +4401,17 @@ dependencies = [
  "unicode-ident",
 ]
 
+[[package]]
+name = "syn"
+version = "3.0.3"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "53e9bae58849f64dfa4f5d5ae372c8341f7305f82a3868709269343628b659a3"
+dependencies = [
+ "proc-macro2",
+ "quote",
+ "unicode-ident",
+]
+
 [[package]]
 name = "sync_wrapper"
 version = "1.0.2"
@@ -4471,6 +4742,21 @@ dependencies = [
  "tokio",
 ]
 
+[[package]]
+name = "tauri-plugin-single-instance"
+version = "2.3.7"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "acba6b5ca527a96cdfcc96ae09b09ccb91ddff5e33978ca6873b96ea16bb404c"
+dependencies = [
+ "serde",
+ "serde_json",
+ "tauri",
+ "thiserror 2.0.18",
+ "tracing",
+ "windows-sys 0.60.2",
+ "zbus",
+]
+
 [[package]]
 name = "tauri-plugin-updater"
 version = "2.9.0"
@@ -4933,9 +5219,21 @@ source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "63e71662fa4b2a2c3a26f570f037eb95bb1f85397f3cd8076caed2f026a6d100"
 dependencies = [
  "pin-project-lite",
+ "tracing-attributes",
  "tracing-core",
 ]
 
+[[package]]
+name = "tracing-attributes"
+version = "0.1.31"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "7490cfa5ec963746568740651ac6781f701c9c5ea257c58e057f3ba8cf69e8da"
+dependencies = [
+ "proc-macro2",
+ "quote",
+ "syn 2.0.114",
+]
+
 [[package]]
 name = "tracing-core"
 version = "0.1.36"
@@ -4985,6 +5283,17 @@ version = "1.19.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "562d481066bde0658276a35467c4af00bdc6ee726305698a55b86e61d7ad82bb"
 
+[[package]]
+name = "uds_windows"
+version = "1.2.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "f2f6fb2847f6742cd76af783a2a2c49e9375d0a111c7bef6f71cd9e738c72d6e"
+dependencies = [
+ "memoffset",
+ "tempfile",
+ "windows-sys 0.61.2",
+]
+
 [[package]]
 name = "unic-char-property"
 version = "0.9.0"
@@ -5134,6 +5443,7 @@ dependencies = [
  "tauri-plugin-fs",
  "tauri-plugin-process",
  "tauri-plugin-shell",
+ "tauri-plugin-single-instance",
  "tauri-plugin-updater",
  "tokio",
  "wasapi",
@@ -5938,6 +6248,15 @@ dependencies = [
  "memchr",
 ]
 
+[[package]]
+name = "winnow"
+version = "1.0.4"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "23b97319f7b8343df12cc98938e5c3eb436064524c8d2b4e30a1d3a36eecdf81"
+dependencies = [
+ "memchr",
+]
+
 [[package]]
 name = "winreg"
 version = "0.55.0"
@@ -6068,6 +6387,76 @@ dependencies = [
  "synstructure",
 ]
 
+[[package]]
+name = "zbus"
+version = "5.19.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "5db4be7c075cb421e4b7ee645541604239bd243ba7c357511f4ff3a74b555907"
+dependencies = [
+ "async-broadcast",
+ "async-executor",
+ "async-io",
+ "async-lock",
+ "async-process",
+ "async-recursion",
+ "async-task",
+ "async-trait",
+ "blocking",
+ "enumflags2",
+ "event-listener",
+ "futures-core",
+ "futures-lite",
+ "hex",
+ "libc",
+ "ordered-stream",
+ "rustix",
+ "serde",
+ "serde_repr",
+ "tracing",
+ "uds_windows",
+ "uuid",
+ "windows-sys 0.61.2",
+ "winnow 1.0.4",
+ "zbus_macros",
+ "zbus_names",
+ "zvariant",
+]
+
+[[package]]
+name = "zbus_macros"
+version = "5.19.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "2990635d09ade6df1868f72f8cac69a876a90981e8bd3c40b1be413f8dc88f40"
+dependencies = [
+ "proc-macro-crate 3.4.0",
+ "proc-macro2",
+ "quote",
+ "syn 3.0.3",
+ "zbus_names",
+ "zvariant",
+ "zvariant_utils",
+]
+
+[[package]]
+name = "zbus_names"
+version = "4.3.4"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "d8bf88b4a3ff53e883001e0e0115b297a9d53c31b9c1edd2bfdd853e3428624e"
+dependencies = [
+ "serde",
+ "winnow 1.0.4",
+ "zvariant",
+]
+
+[[package]]
+name = "zcheapstr"
+version = "1.1.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "d1afec51604565183aeb5c54c20aeab286120d4e4460f7f76e3e8bb8c0d99473"
+dependencies = [
+ "serde",
+]
+
 [[package]]
 name = "zerocopy"
 version = "0.8.33"
@@ -6165,3 +6554,44 @@ name = "zmij"
 version = "1.0.16"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "dfcd145825aace48cff44a8844de64bf75feec3080e0aa5cdbde72961ae51a65"
+
+[[package]]
+name = "zvariant"
+version = "5.14.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "b5e28c25bd8bb8da5a1f3e7065d0c156b9ee9a7973adf78b0e35eaefdf3b1b5c"
+dependencies = [
+ "endi",
+ "enumflags2",
+ "serde",
+ "winnow 1.0.4",
+ "zcheapstr",
+ "zvariant_derive",
+ "zvariant_utils",
+]
+
+[[package]]
+name = "zvariant_derive"
+version = "5.14.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "d496a145685283b67e232bd9e47377f6b60ad9d51e3601b23867f77c42477f96"
+dependencies = [
+ "proc-macro-crate 3.4.0",
+ "proc-macro2",
+ "quote",
+ "syn 3.0.3",
+ "zvariant_utils",
+]
+
+[[package]]
+name = "zvariant_utils"
+version = "4.0.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "629d80ece222cad20fe0e8741be493c4ab166acf3b85341bdc2cdbcfd8f3c2d6"
+dependencies = [
+ "proc-macro2",
+ "quote",
+ "serde",
+ "syn 3.0.3",
+ "winnow 1.0.4",
+]
diff --git a/tauri/src-tauri/Cargo.toml b/tauri/src-tauri/Cargo.toml
index ab69555a5..1084c27a3 100644
--- a/tauri/src-tauri/Cargo.toml
+++ b/tauri/src-tauri/Cargo.toml
@@ -52,6 +52,7 @@ webkit2gtk = "2.0"
 [target.'cfg(not(any(target_os = "android", target_os = "ios")))'.dependencies]
 tauri-plugin-updater = "2.0"
 tauri-plugin-process = "2.0"
+tauri-plugin-single-instance = "=2.3.7"
 # Observe-only global keyboard tap. Covers macOS, Windows, and Linux
 # (evdev) with left/right modifier fidelity, which is the hard
 # requirement the chord engine needs. keytap is our own crate
diff --git a/tauri/src-tauri/src/main.rs b/tauri/src-tauri/src/main.rs
index 0f44ac90f..eb3d4c51a 100644
--- a/tauri/src-tauri/src/main.rs
+++ b/tauri/src-tauri/src/main.rs
@@ -1381,7 +1381,20 @@ async fn debug_clipboard_roundtrip(
 
 #[cfg_attr(mobile, tauri::mobile_entry_point)]
 pub fn run() {
-    tauri::Builder::default()
+    let builder = tauri::Builder::default();
+
+    // Register this before every other plugin so a second launch exits before
+    // it can create another dictate window or global hotkey monitor.
+    #[cfg(desktop)]
+    let builder = builder.plugin(tauri_plugin_single_instance::init(|app, _args, _cwd| {
+        if let Some(window) = app.get_webview_window("main") {
+            let _ = window.show();
+            let _ = window.unminimize();
+            let _ = window.set_focus();
+        }
+    }));
+
+    builder
         .plugin(tauri_plugin_dialog::init())
         .plugin(tauri_plugin_fs::init())
         .plugin(tauri_plugin_shell::init())
@@ -1535,49 +1548,67 @@ pub fn run() {
         .on_window_event({
             let closing = std::sync::Arc::new(std::sync::atomic::AtomicBool::new(false));
             move |window, event| {
-            if let WindowEvent::CloseRequested { api, .. } = event {
-                // If we're already in the close flow, let it proceed
-                if closing.load(std::sync::atomic::Ordering::SeqCst) {
-                    return;
-                }
-                closing.store(true, std::sync::atomic::Ordering::SeqCst);
+                if let WindowEvent::CloseRequested { api, .. } = event {
+                    // Closing the overlay should never begin the application-wide
+                    // shutdown flow. Only the main window represents app close.
+                    if window.label() != "main" {
+                        return;
+                    }
 
-                // Prevent automatic close so frontend can clean up
-                api.prevent_close();
+                    // If we're already in the close flow, let it proceed
+                    if closing.load(std::sync::atomic::Ordering::SeqCst) {
+                        return;
+                    }
+                    closing.store(true, std::sync::atomic::Ordering::SeqCst);
 
-                // Emit event to frontend to check setting and stop server if needed
-                let app_handle = window.app_handle();
+                    // Prevent automatic close so frontend can clean up
+                    api.prevent_close();
 
-                if let Err(e) = app_handle.emit("window-close-requested", ()) {
-                    eprintln!("Failed to emit window-close-requested event: {}", e);
-                    window.close().ok();
-                    return;
-                }
+                    // Emit event to frontend to check setting and stop server if needed
+                    let app_handle = window.app_handle().clone();
 
-                // Set up listener for frontend response
-                let window_for_close = window.clone();
-                let closing_for_timeout = closing.clone();
-                let (tx, mut rx) = mpsc::unbounded_channel::<()>();
+                    // Release the OS-level listener immediately. Frontend/backend
+                    // cleanup may take several seconds, but F8/F9 must become inert
+                    // as soon as the user closes the app.
+                    #[cfg(desktop)]
+                    if let Err(e) = disable_hotkey(app_handle.state::<HotkeyState>()) {
+                        eprintln!("Failed to disable hotkey during close: {e}");
+                    }
 
-                let listener_id = window.listen("window-close-allowed", move |_| {
-                    let _ = tx.send(());
-                });
+                    if let Err(e) = app_handle.emit("window-close-requested", ()) {
+                        eprintln!("Failed to emit window-close-requested event: {}", e);
+                        app_handle.exit(0);
+                        return;
+                    }
 
-                tauri::async_runtime::spawn(async move {
-                    tokio::select! {
-                        _ = rx.recv() => {
-                            window_for_close.close().ok();
-                        }
-                        _ = tokio::time::sleep(tokio::time::Duration::from_secs(5)) => {
-                            eprintln!("Window close timeout, closing anyway");
-                            window_for_close.close().ok();
+                    // Set up listener for frontend response
+                    let window_for_close = window.clone();
+                    let app_for_exit = app_handle.clone();
+                    let (tx, mut rx) = mpsc::unbounded_channel::<()>();
+
+                    let listener_id = window.listen("window-close-allowed", move |_| {
+                        let _ = tx.send(());
+                    });
+
+                    tauri::async_runtime::spawn(async move {
+                        let timed_out = tokio::select! {
+                            _ = rx.recv() => false,
+                            _ = tokio::time::sleep(tokio::time::Duration::from_secs(5)) => {
+                                true
+                            }
+                        };
+                        if timed_out {
+                            eprintln!("Window close timeout, exiting anyway");
                         }
-                    }
-                    window_for_close.unlisten(listener_id);
-                    closing_for_timeout.store(false, std::sync::atomic::Ordering::SeqCst);
-                });
+                        window_for_close.unlisten(listener_id);
+                        // Closing only the main webview strands the hidden dictate
+                        // window and its hotkey thread. Exit the whole Tauri app so
+                        // every window and listener is torn down together.
+                        app_for_exit.exit(0);
+                    });
+                }
             }
-        }})
+        })
         .build(tauri::generate_context!())
         .expect("error while building tauri application")
         .run(|app, event| {