There is technically no such thing as "FLAC 11" as a codec version. The FLAC codec has been stable for years.
What "11" likely means:
What to look for in the file specs: Since you want FLAC, check the details of the download to ensure quality: janet jackson 8 albums inc greatest hits flac 11
A Forensic Analysis of the Search Query “janet jackson 8 albums inc greatest hits flac 11” — Implications for Digital Music Piracy and Archival Practices There is technically no such thing as "FLAC
If you’re seeking this specific set, here’s how to proceed ethically and with quality: What to look for in the file specs: