Question regarding "identifiers" in "dds.pf.tmLanguage.json"

[richardm90]

I was viewing the DDS source for a physical file the other day and noticed that the "R" in position 29 was not highlighted when the length of the field name is 10 characters long. If I remove the whole "identifiers" section from the syntax file then it works as expected. I couldn't see any specific documentation in the Language Configuration Guide that mentioned "identifiers" so was curious as to what this definition actually does. Does anyone know? As an aside the pattern name within the "identifiers" section is identifier.other.dds.lf.identifiers rather than identifier.other.dds.pf.identifiers.