给 GitHub 设置了 Two-factor authentication，添加 fallback SMS number 时发现不支持 +86 号码

虽然我近期用 Microsoft Authenticator app 给 GitHub 设置了两步验证，但是最近还是提醒我好几次说要添加更多安全方法，于是我就添加了 Security keys ，在我准备添加手机号接收验证码短信时却在 select 组件中找好久没找到 +86 的号码前缀，ohhhhh ，原来是不支持啊。

为什么不支持？

以下是支持的列表

United States +1
Aland Islands +358
Algeria +213
Angola +244
Anguilla +1264
Australia +61
Austria +43
Bahamas +1
Bahrain +973
Bangladesh +880
Belarus +375
Belgium +32
Benin +229
Bolivia +591
Bosnia and Herzegovina +387
Brunei +673
Bulgaria +359
Burundi +257
Cambodia +855
Canada +1
Cape Verde +238
Cayman Islands +1345
Christmas Island +61
Cocos +61
Congo, Dem Rep +243
Croatia +385
Cyprus +357
Czech Republic +420
Denmark +45
Dominica +1767
Dominican Republic +1
Ecuador +593
Equatorial Guinea +240
Estonia +372
Finland/Aland Islands +358
France +33
Gambia +220
Georgia +995
Germany +49
Ghana +233
Gibraltar +350
Greece +30
Guatemala +502
Guyana +592
Hungary +36
Iceland +354
Indonesia +62
India +91
Ireland +353
Israel +972
Italy +39
Ivory Coast +225
Jamaica +1876
Japan +81
Jordan +962
Kazakhstan +7
Kuwait +965
Latvia +371
Libya +218
Liechtenstein +423
Lithuania +370
Luxembourg +352
Madagascar +261
Malawi +265
Malaysia +60
Maldives +960
Mali +223
Malta +356
Mauritius +230
Mexico +52
Monaco +377
Montenegro +382
Montserrat +1664
Mozambique +258
Namibia +264
Netherlands +31
Netherlands Antilles +599
New Zealand +64
Nigeria +234
Norway +47
Philippines +63
Poland +48
Portugal +351
Qatar +974
Romania +40
Rwanda +250
Senegal +221
Serbia +381
Seychelles +248
Singapore +65
Slovakia +421
Slovenia +386
South Africa +27
South Korea +82
Spain +34
Sri Lanka +94
St Lucia +1758
Sudan +249
Sweden +46
Switzerland +41
Taiwan +886
Tanzania +255
Togo +228
Trinidad and Tobago +1868
Turks and Caicos Islands +1649
Uganda +256
United Arab Emirates +971
United Kingdom +44
United States +1
Uzbekistan +998
Venezuela +58