Since last December, the FLAC spec finally made it into an internet standard as RFC 9639. Therefore, it’s a suitable time to update the spec comments in the FlacLoader.

• Update all references to the draft specification and other references, where they can be replaced by a link to the RFC or some section of it. This includes the Application block ID registry, which is now managed by IANA instead of Xiph.

  Update all section numbers.

  Update naming conventions, where they have changed. A Ctrl-F on FLAC-specific terms in the RFC should be enough to figure this one out.
  To pick up a draggable item, press the space bar. While dragging, use the arrow keys to move the item. Press space again to drop the item in its new position, or press escape to cancel.

Feel free to ping me if you make a PR about this and I’ll review it.