Constant libnotcurses_sys::NCALPHA_BGDEFAULT_MASK

pub const NCALPHA_BGDEFAULT_MASK: u32 = crate::bindings::ffi::NC_BGDEFAULT_MASK; // 0x4000_0000u32

If this bit is set, we are not using the default background color

See the detailed diagram at NcChannels

Note: This can also be used against a single NcChannel