Function isAliasPreserved

background.js:1112–1116

(state, email)

}

function isAliasPreserved(state, email) {
  const normalizedEmail = String(email || '').trim().toLowerCase();
  if (!normalizedEmail) return false;
  return Boolean(getPreservedAliasMap(state)[normalizedEmail]);
}

function getEffectiveUsedEmails(state) {
  return toNormalizedEmailSet(getManualAliasUsageMap(state));