Allow for Non-Standard Charset Name

[s25g5d4]

Hello,

I encountered a server that returns content-disposition: attachment; filename="file.png"; filename*=utf8''file.png which is, according to RFC 5987, malformed because the charset should be utf-8, rather than utf8. When trying to decode content-disposition, it will fail at

content-disposition/index.js

Line 286 in 9908a22

throw new TypeError('unsupported charset in extended field')

. It is not my server and I have no way to ask them to change, so if you can fix this (either by accept utf8 or fallback to filename) that would be appreciated.

[dougwilson]

Yea, I agree that there needs to be at least one of those options (the very minimum to be able to ignore the unknown encoding because there wasn't a parse error, it parsed fine but just didn't know how to decode).