Tray Minimizer

Right-click any window's minimize button and that window goes to the system tray instead of the taskbar. Left-click its tray icon to bring it back.

One executable. No installer, no DLL injection, no runtime to download, no telemetry.

Why

Windows has no way to park a window in the tray. The tools that add one, RBTray among them, ask the window where its minimize button is, and apps that paint their own title bar (Windows Terminal, WinUI apps, some Office windows) answer that they have none, so the right-click falls through. Tray Minimizer handles those by working out where the button must be from the window's frame and its DPI, so the modern frames work as well as the classic ones.

Install

1. Download TrayMinimizer.zip from Releases.
2. Right-click the zip, choose Properties, tick Unblock, then extract it anywhere.
3. Run TrayMinimizer.exe. Its icon (a blue down arrow) lands under the ^ arrow next to the clock.
4. Right-click that icon and tick Start with Windows if you want it at every logon.

It is portable. Outside its own folder it writes one setting under HKCU\Software\TrayMinimizer and, only if you tick it, the startup entry. It needs .NET Framework 4, which every supported version of Windows already has, and it is built for 64-bit Windows.

Usage

• Right-click a window's minimize button: the window is hidden and a tray icon appears with the window's own icon and title.
• Left-click that tray icon: the window comes back (maximized state is preserved) and gets focus.
• Right-click that tray icon: Restore, or Close window.
• The Tray Minimizer icon itself has: Restore all windows, Custom title bar mode, Start with Windows, How it works, Exit.

Exiting restores every window it is holding, so nothing can get stranded. It also restores on logoff, shutdown, and unhandled errors.

Startup

Start with Windows on the tray menu writes HKCU:\Software\Microsoft\Windows\CurrentVersion\Run under the value TrayMinimizer. Untick it there, or remove it by hand with:

Remove-ItemProperty 'HKCU:\Software\Microsoft\Windows\CurrentVersion\Run' -Name 'TrayMinimizer'

How it works

A WH_MOUSE_LL low-level mouse hook watches for right-button down/up. A low-level hook runs in this process, so nothing is loaded into anyone else's.

On button-down it resolves the top-level window under the cursor and sends it WM_NCHITTEST (100 ms SMTO_ABORTIFHUNG timeout, so a hung app can never stall the mouse), then decides by two paths:

1. Standard frames answer HTMINBUTTON and are handled directly.
2. Custom title bars (see below) answer plain HTCAPTION across the entire strip, buttons included. For those, the button is located geometrically: third slot in from the right edge of the DWM extended frame bounds, using standard Windows 11 caption metrics (46x32 DIP) scaled by that window's own DPI, and only if the window has WS_MINIMIZEBOX. DWMWA_EXTENDED_FRAME_BOUNDS is used rather than GetWindowRect because the latter includes the invisible resize border and is wrong when maximized.

Button-up confirms by proximity (same window, cursor within 12 px of the press) rather than hit-testing a second time. An earlier version did re-test, and a timed-out round trip to a busy app silently ate the click. Both clicks are swallowed so no system menu appears.

The window is hidden immediately; the tray icon is built afterward, since fetching a packaged app's icon can take a few hundred ms and the click should feel instant. Real work is deferred off the hook callback with BeginInvoke.

A 2-second sweep drops tray icons for windows that were closed or reappeared on their own. The hook is reinstalled every 10 minutes, since Windows can silently drop a low-level hook whose callback ever ran long.

Custom title bar mode

On by default, toggle in the tray menu, stored at HKCU:\Software\TrayMinimizer\CustomTitleBarFallback.

Needed for Windows Terminal, WinUI apps, and some Office windows. Verified on Windows Terminal: it reports HTCAPTION (2) over minimize, maximize, and close alike, and exposes no caption buttons through UI Automation at all (only its tab close button and scrollbar), so position is the only way to find the button.

Turn it off if a right-click near the top-right corner of a window ever does something you did not expect.

Known limits

• Windows owned by elevated (admin) processes are skipped. UIPI blocks the hit-test message from a non-elevated process, so the right-click behaves normally there. Run Tray Minimizer elevated if you need it to cover admin windows.
• Apps whose custom caption buttons are not standard-sized and not exposed to WM_NCHITTEST are not detected. Discord is one example: it draws narrower buttons than the Windows metric, so the geometric slot does not line up.
• Chrome, Edge, Explorer, Notepad, Office, and standard Win32/UWP frames all use path 1 and work directly.

Build from source

powershell -ExecutionPolicy Bypass -File .\build.ps1

build.ps1 compiles with the C# compiler that ships inside C:\Windows\Microsoft.NET, so no SDK or Visual Studio is needed. If an instance from this folder is running it is asked to quit first (every parked window is restored), then relaunched.

License

MIT, see LICENSE.