Missing country flags

[Vampire]

The following reserved ISO-3166-1 country codes do not have the according flag Emoji.
As other reserved country codes have their respective flag included, I'd like to ask for these also being added.

AN (Netherlands Antilles) 🇦🇳
BU (Burma) 🇧🇺
CS (Serbia and Montenegro) 🇨🇸
EZ (Eurozone)
FX (France, Metropolitan) 🇫🇽
NT (Saudi Arabian–Iraqi neutral zone) [maybe half Saudi Arabia, half Iraq] 🇳🇹
SF (Finland) 🇸🇫
SU (USSR) 🇸🇺
TP (East Timor) 🇹🇵
UK (United Kingdom) 🇺🇰
YU (Yugoslavia) 🇾🇺
ZR (Zaire) 🇿🇷

[Crissov]

If you went by deprecated region codes in CLDR, i.e. the resource UTS#51 actually references (through LDML), you would have to add DD, QU and YD, but remove UK from that list. You could also add the 2-letter macroregion codes EZ and QO as well as unknown status code ZZ.

Most of these do not make much sense to support, though, because they are aliases for current codes. Emojitwo supports SU, for what it’s worth. UTS#51 does not recommend any of these for general interchange.

Google’s Noto Color Emoji font has a white flag with an question mark at some PUA code point. ZZ makes more sense for that. They also display it for all unsupported RIS pairs which results in bad fallback behavior: two letters would usually be better.

[Vampire]

• DD and YD are officially deleted and can be re-assigned, so I'd not add them.
• QO, QU and ZZ are user-assigned codes so could mean different things, so I'd not add them.
• Regarding UK and SF, they are both in neither of the sections in the link you provided, but anyway they are exceptionally reserved codes, so I keep them in the list.
• You are right about EZ though, so I added it to the list.

You are maybe right that most of these are just aliases for other entries, yet in my opinion it would make sense to support them. If you e. g. have a software like Discord, that just searches for the matching file, it cannot show the correct flag without a manual mapping that every user of twemoji would have to implement himself. I think it would make more sense if twemoji just also has these flags present like other reserved cases then the user of the lib does not need to do anything special to use them.