Per Copilot & Codex review on PR #5527:
- performercredit was registered as a plain string mapping, but PERFORMER
is type:pair ('PERFORMER:instrument'). The credit form needs the same
pair structure to be meaningful, and processPerformers doesn't read it
either way. Better to remove the misleading mapping than ship dead
config that suggests support we don't have.
- TagComposersCredit and TagLyricistsCredit (plural variants) were never
consumed by any code path — only the singular TagComposerCredit and
TagLyricistCredit are wired into roleMappings.
Both can be added back when the underlying feature is actually
implemented.
c413d6510e