Sigil currently recognizes the following media types (each one followed by a list of preferred file extensions - with multiple entries if needed).
When there are multiple media-types for the exact same file type, the entries preceded by an "*" are the most recommended by both the epub 3.3 spec and/or the very latest iana (2025) list (
https://www.iana.org/assignments/med...ia-types.xhtml).
Please give this list a once over and let me know if you have run into epubs that make use of additional media-types that you think Sigil should recognize.
Also if you have run into older mime/media types not in this list that you think should also be recognized please let me know.
Thanks