fn set_taskbar_hidden(hwnd: *mut c_void, hidden: bool)Expand description
Toggle WS_EX_TOOLWINDOW on a window’s extended style so it appears (or doesn’t) in the taskbar / Alt+Tab. We use this so pre-warmed pool windows stay invisible to the user, then re-enter the taskbar when promoted to a real torn-off window.
Per Win32 docs, changing the ex-style after creation only updates the taskbar reliably if the window is hidden + reshown. We do that hide/show cycle here with SWP_FRAMECHANGED so the change takes effect even if SW_HIDE was already implicit.