Codes which are part of private use code ranges are not recognised

[nikkiwd]

Private use codes such as XA which are defined as part of code ranges are not recognised, whereas those like AA which are not part of ranges work fine.

Works:
https://r12a.github.io/app-subtags/index?lookup=AA

Type: region
Subtag: AA
Description: Private use
Added: 2005-10-16

Does not work:
https://r12a.github.io/app-subtags/index?lookup=XA

Type: region
Subtag: XA..XZ
Description: Private use
Added: 2005-10-16