An or note included by the person who uploaded the file.

A request for a or "paper" explaining the contents of the update or the specific changes in Part 3. 21 patch notes? New info on update 1.21! - Way of the Hunter

The file name you provided follows a common pattern used in digital distribution, particularly for large updates or community-made mods: : Indicates the game version (1.21).

: A common archive file format used to compress data. You will typically need all parts (part1, part2, and part3) in the same folder to extract them using software like WinRAR or 7-Zip. Note on "Long Paper"

The update allows players to see animals as young deer, providing an opportunity to "mark" them on a notepad or toolkit to track their growth over time.

The phrase "long paper" does not appear to be a standard technical term associated with the game's official updates. It may refer to:

This feature helps players distinguish specific animals within a herd, making it easier to keep track of their development and health. Understanding the File Name