Name ID 3 also needs to be changed (unique identifier)

[me-ans]

The unique identifier also needs to be changed. Adding this to the code fixes it (line 94):

 elif record.nameID == 3:
       record.string = nameID6_string

The issue made a font unusable by some applications.
Hope it helps!

[chrissimpkins]

Thanks! Do you have information on the applications where this is important?

[me-ans]

An application has crashed here that uses the unique ID internally to distinguish fonts. Another issue may arise when the OS uses this information to check for conflicts, duplicates, etc.

Open Font Book on macOS and see how all other fonts consistently use the ID (as far as I could see, they are all using the PostScript ID for this). It's probably similar on Windows.

[me-ans]

At any rate, it would be weird to keep the OLD name as the unique ID when all other names have changed.