Findings about the new Emoji feature in Serato DJ Pro v4.x

[LyricsLover]

As I wrote here:

Serato 4.0 now supports song ratings!

In Serato, you can right-click on a track and "Select Rating Emoji" to choose the Emoji displayed individually for each music track. It looks like this: [2025.12.12 -Emoji-Rating per track] The value in POPULARIMETER remains the same. But the chosen Emoji will be written into the tracks metadata too. Example for MP3: [2025.12.12 - SERATO RATING EMOJI #2] [2025.12.12 - 10-27-42 - SERATO RATING EMOJI #1] The field name used for MP3 is SERATO RATING EMOJI. The funny thing: These Emojis ar…

you can set Rating-Emojis in the new "Serato DJ Pro" version since version v4.0

A marketing title for this feature is "This next track is a four watermelon banger".

Unfortunately it is not clear why we cannot successfully set the Serato Rating Emoji field (case-sensitive!) in Mp3tag and fill the POPULARIMETER field with Serato|nnn|0 and the numbers 1 (1-star), 64 (2-star), 128 (3-star), 196 (4-star) or 255 (5-star).
This has been tested with the MP3 music format.

If we do that initially in Mp3tag and import the track into Serato, the Rating will be displayed as follows:
a) There will be no visible rating at all
or
b) The value will be displayed with stars (but without Emojis)
or
c) Both, the number of Emojis and the Emojis itself are visibly perfect
However, each of the above conditions can appear with or without the option to adjust the number of Emojis or the Emojis itself in Serato. I could not find a way to reproduce that behaviour.

After several hours of testing, I only found these reproducable facts so far:

1. Mp3tag always writes the Emoji values ("surrogate pair") in the case-sensitive Serato Rating Emoji field with 00 00 at the end. These 00 00 are known as a 'terminator'.
2. Serato writes the same Emoji values but without 00 00 at the end.
3. The Emoji will only be writtten in a new, case-sensitive TXXX Serato Rating Emojj field from the Tag Panel, not from Alt + T (Extended Tags).

Other findings that are not fully reproducible or explainable:
I) The "easier" the Emojis are, the more interchangeable they seem.

A "simple" Emoji like is represented by Unicode: U+1F3C6 or
UTF‑16LE Hex: 3C D8 C6 DF

A "complicated" Emoji like 👩🏿‍❤️‍👩🏻 (Couple with Heart: Woman, Woman, different skin tones) is represented by
= U+1F469 + U+1F3FF (woman with dark skin tone), followed by
ZWJ = U+200D, followed by
= U+2764 + U+FE0F (heart with Variation Selector), followed by
ZWJ = U+200D, followed by
= U+1F469 + U+1F3FB (woman with light skin tone)
or UTF-16LE Hex:
3D D8 69 DC 3C D8 FF DF 0D 20 27 26 0F FE 0D 20 3D D8 69 DC 3C D8 FB DF

II) Sometimes the Serato right-click function "Re-scan File Info" re-reads the Rating correctly, sometimes it does nothing

III) Sometimes the Serato right-click function "Analyze Files" re-reads the Rating(!), sometimes it does nothing. I don't know if these Serato analyze-settings have an impact:

IV) Deleting a file from the Serato library and adding it again does not guarantee that the Rating will always be read correctly. It seems that the reading of the tag content sometimes "needs some time".

So far, I have not found a guaranteed method of initially setting an Emoji in MP3tag that can be changed in Serato.

I would be very grateful if anyone who knows more about this case or is aware of a procedure that would allow us to interchange the Emojis could let me know.