for some reason, the ETF features i applied to my skin work perfectly in 1.21.3 but not at all in 1.21.4, both in fabric and forge. i used a test resource pack to confirm that mob emissives work in all versions, and i've tested with and without other mods in the modrinth profile.
also in 1.21.4 whenever i open the player skin features menu, the options are all greyed out. when i click to enable them, it changes which skin is selected to my previously used skin, also with no working ETF options. i'm not sure if these two issues are related.