Relates to WEB-840
The bug
The maximum file size of skins was set to 16384 for the page https://minecraft.net/en-us/profile/?ref=bm. However, apparently this was only hardcoded in the JavaScript code of the page:
validateSkinFile: function(e) { return new r.Promise(function(t, n) { var o; if ("png" !== e.name.match(/\.([^\.]+)$/)[1].toLowerCase()) return void n(new Error("File is not an .png")); if (e.size > 16384) return void n(new Error("File is too large")); ...
The API still uses 24576 bytes as maximum value:
{"error":"IllegalArgumentException","errorMessage":"Max allowed size is 24576 bytes"}