Clock actions, tray and accessibility

Action behavior table

Source	Result	Notes
Left press and release inside an overlay	One calendar action: a single `SendInput` batch Win down, N down, N up, Win up	Mouse capture pairs press and release; release outside the slot or lost capture does nothing
A second activation within 400 ms	Ignored	Win+N toggles the flyout; a double click must not open and close it
Activation while Ctrl, Shift, Alt, Win or N is physically held	Nothing sent, overlay unchanged, cooldown not consumed	A held modifier would form a different shortcut; the user’s keys are never released by the app
`SendInput` inserts fewer than four events	Accepted key-downs are released, then all overlays are hidden and `Reason::ActionFailed` is recorded; no retry	The native clock stays reachable. Pause then Resume (or an Explorer restart) tries again
Right click / touch press-and-hold on the overlay	Fixed menu at the pointer	`WM_CONTEXTMENU`, one menu per gesture
Tray icon: context menu, mouse select, keyboard select (`NIN_SELECT`, `NIN_KEYSELECT`, `WM_CONTEXTMENU`)	The same fixed menu at the icon’s anchor	Win+B reaches the notification area from the keyboard; a menu that just closed is not reopened by the second event Windows may send
Menu Settings	`Platform::open_settings` → loop → `SettingsWindow::show_or_focus`	Never a second window
Menu Pause clock replacement / Resume clock replacement	Core `Event::SetPaused`: every overlay is hidden (native clock shows) / shown again; tooltip reads “ElevenClock (paused)”	Session only: not persisted, a new process starts running
Menu Exit	`Quit`: overlays, tray icon, hooks and helper are removed; native clock untouched	Same path as the Settings Exit button
UIA Invoke on the overlay element	Same as a left click (queued to the UI thread)	See below
Anything while paused, fullscreen-hidden, faulted, or for a stale generation	Ignored	The runtime re-checks the reducer’s `OverlayState` before acting

Out of scope and absent: arbitrary commands, double/middle-click customization, keyboard shortcuts beyond standard menu navigation, a duplicated notification counter, shell injection, synthetic mouse relay. The menu has exactly three commands (MenuCommand).

Calendar strategy

On tested builds, UIA Invoke on the native clock returned success without opening the flyout, while one deliberate Win+N opened it. The production action is therefore the deliberate keyboard batch only. It runs on the UI thread, needs no COM and cannot block the message loop; UIA is not used to discover or invoke the native clock from the click path. If a later build proves a supported UIA invoke, only Platform::open_calendar changes.

UI Automation provider

One element per overlay window (accessibility.rs, IRawElementProviderSimple + IInvokeProvider, server-side, host provider from the HWND).
Name = displayed text in reading order ("12:34, 14/10/2026", trimmed, at most 256 characters). ControlType = Button. AutomationId = ElevenClock.Clock. Help text “Opens the calendar and notifications”. Not keyboard focusable.
Pattern choice: Invoke only. There is no Value pattern (a second copy of the same text) and no UIA event is ever raised, so a per-second format cannot produce a stream of announcements; a screen reader reads the current text on demand.
UIA calls the provider on its own thread. The provider holds only a mutex-guarded string, an atomic liveness flag and a window id; Invoke posts an interaction to the UI thread and returns. After UiaDisconnectProvider (called before the window is destroyed) every method returns UIA_E_ELEMENTNOTAVAILABLE.
A hidden overlay (paused, fullscreen, fault, Explorer loss) is not in the UIA tree, so Explorer’s own clock element is the only one a screen reader sees.

Keyboard access

The overlay is non-activating, so it cannot be tabbed to. Keyboard users reach Settings, Pause/Resume and Exit through the notification-area icon (registered with NOTIFYICON_VERSION_4; keyboard activation and the context-menu key open the same menu), and through Start-menu relaunch for Settings. The Win32 popup menu provides arrow keys, Enter and Escape and native UIA/MSAA exposure.

Explorer restart

Runtime calls Platform::restore_tray once at start and from check_shell, the single existing path run for TaskbarCreated and for a changed Explorer PID/creation time. There is no timer or retry of its own. If Explorer is not ready, Shell_NotifyIconW(NIM_ADD) fails quietly and the TaskbarCreated broadcast that follows tries again; a repeated restore uses NIM_MODIFY and never stacks a second icon.

Hooks for Settings, Support and UI tests

Settings: the menu’s Settings item calls Platform::open_settings, which sets the loop’s existing SHOW_SETTINGS flag; pump then calls SettingsWindow::show_or_focus after the current input. WM_SHOW_SETTINGS (second launch) uses the same flag.
Support: Runtime::diagnostics() carries paused and, per taskbar, Reason::ActionFailed(reason) with the exact SendInput failure text.
UI tests: AutomationId == "ElevenClock.Clock"; overlay class ElevenClock.Overlay; tray icon id 1 on the host window class ElevenClock.Runtime.Host; menu item ids 1..3.

Known limitations

The menu is modal: while it is open the overlay clock does not repaint (timers queue and run when it closes).
Narrator may see both the overlay element and Explorer’s own clock element while the overlay is shown; not de-duplicated without modifying Explorer.
A UIA client that invokes the element cannot learn that the later calendar action failed (the call returns once queued); the failure is visible in diagnostics.
Menu strings are fixed English.
Pause is deliberately not persisted.