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app/store/migrations/067.ts

@@ -4,7 +4,10 @@ import { migration66 } from './066';
  * Migration for ensuring that all internal accounts have the correct scopes
  * Re-uses logic from migration 66
  * We have to re-run 66 as 67 because the values for the scopes changed
- * and users who already had 66 ran would not have the updated scope values
+ * and users who already had 66 ran would not have the updated scope values.
+ * The migration 66 was initially injecting a CAIP-2 namespace (eip155 for EVM EOA) rather than a full scope (eip155:0).
+ * We now require full scopes (namespace:chain-id) for all Internal Accounts.
+ * See https://github.com/MetaMask/accounts/pull/165 for more details.
  */
 export default function migrate(state: unknown) {
   return migration66(state, 67);