#617 renamed HDR/4K burn-in refusals to subtitle_conversion_unsupported when the subtitle alone forced adaptation, but terminalAllowsAlternateFileV3 still only recognized the old HDR/4K reasons. Selecting a PGS track on an HDR source therefore skipped the SDR alternate and returned adaptation_unavailable. Co-authored-by: Quick <Quick104@users.noreply.github.com>