Function parse_custom_destinations_checked 

pub fn parse_custom_destinations_checked(
    data: &[u8],
    filename: Option<&str>,
) -> Result<JumpList, JumplistError>

Parse a *.customDestinations-ms Jump List, surfacing the structural reason for a failure.

• Err(JumplistError::BadCustomFormatVersion { found }) — the 4-byte header format version is not the expected value; found is what was read.
• Ok(JumpList) — a parsed Jump List (entries in flat file order).