NETWMSTATEFULLSCREEN

NETWMSTATEFULLSCREEN is a NetWM hint used in the X Window System to indicate whether a window should be displayed in fullscreen mode. This hint is part of the Extended Window Manager Hints (EWMH) specification, which provides a standardized way for window managers to communicate with applications. When a window manager receives the NETWMSTATEFULLSCREEN hint, it interprets it as a request to allocate the entire screen area to the specified window, typically hiding all other window decorations, panels, and other user interface elements. This is commonly used for applications such as video players, games, and presentations.

The hint is communicated via the `_NET_WM_STATE` atom. If the `_NET_WM_STATE_FULLSCREEN` atom is present in the `_NET_WM_STATE` property of a window, the window manager understands that the application desires fullscreen display. Conversely, if this atom is removed, the window manager can revert the window to its previous state, which may involve restoring window decorations and returning it to a tiled or floating position. Applications that support this hint can dynamically toggle fullscreen mode in response to user input or other events, providing a more immersive user experience. Not all window managers strictly adhere to or implement this hint, but it is widely supported in modern desktop environments.