XCB_INPUT_XI_EVENT_MASK_FOCUS_OUT

Undocumented in source but is binding to C. You might be able to learn more by searching the web for its name.
extern (C)
alias XCB_INPUT_XI_EVENT_MASK_FOCUS_OUT = xcb_input_xi_event_mask_t.XCB_INPUT_XI_EVENT_MASK_FOCUS_OUT

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