Are there any plans for supporting ID3v2.4 tags at the end of a file (reading and writing)?

General Discussion
1

Are there any plans for supporting ID3v2.4 tags at the end of a file (reading and writing)?

2

and what would be the use-case?
AFAIK V2.4 tags can be a combination of prepended and appended tags and if they are appended the prepended part has to have a SEEK frame, so there cannot be appended tags exclusively.
See also
https://mutagen-specs.readthedocs.io/en/latest/id3/id3v2.4.0-structure.html#tag-location

3

Thanks for reply.

I am using smart speaker. If the mp3 file with ID3 V2.3 tag or ID3V2.4 prepended tag, then it will delay to play, since the tag in the front of file.

4

As you can see from the spec, any ID3V2 tags will all ways be prepended and only parts can optionally be appended.
So, you either use tags that are always at the end like ID3V1 tags (and all the shortcomings in respect to fields, covers and tag length) or you ask your player supplier if he can implement a decent decoder that can cope with perfectly standard conform tags.

5

I think you're misunderstanding the spec. It also allows for only ID3v2.4 to be appended (without a prepended ID3v2 tag). In this case, the app would need to seek for an 3DI ID3v2 footer identifier (which then includes the size of the whole tag).

It's not planned at the moment.

Do you have any experience with appended ID3v2.4 tags? Given the lack of support for prepended ID3v2 tags, it's likely that there is a delay when the track ends and is about to start the next.