/// This is the Vietnamese encoding for Windows.
///
/// [Index visualization](https://encoding.spec.whatwg.org/windows-1258.html),
/// [Visualization of BMP coverage](https://encoding.spec.whatwg.org/windows-1258-bmp.html)
///
/// This encoding matches the Windows code page 1258 when used in the
/// non-normalizing mode. Unlike with the other single-byte encodings, the
/// result of decoding is not necessarily in Normalization Form C. On the
/// other hand, input in the Normalization Form C is not encoded without
/// replacement. In general, it's a bad idea to encode to encodings other
/// than UTF-8, but this encoding is especially hazardous to encode to.