diff --git a/README.md b/README.md
index a4b34b2..2b880b1 100644
--- a/README.md
+++ b/README.md
@@ -301,7 +301,10 @@ For backwards compatibility with v1, the non-stringified `message` is the same a
 
 Minor Breaking changes (with a major version bump):
 
--   v3.0.0 - reworked error messages (also available in v2.1.0 as `client_message`)
--   v2.0.0 - changes from the default `issuers = ["*"]` to requiring that an issuer (or public jwk for verification) is specified
+-   v3.0.0
+    -   reworked error messages (also available in v2.1.0 as `client_message`)
+    -   started using `let` and template strings (drops _really_ old node compat)
+-   v2.0.0
+    -   changes from the default `issuers = ["*"]` to requiring that an issuer (or public jwk for verification) is specified
 
 See other changes in [CHANGELOG.md](./CHANGELOG.md).
diff --git a/lib/errors.js b/lib/errors.js
index 26cf543..820f5a4 100644
--- a/lib/errors.js
+++ b/lib/errors.js
@@ -22,8 +22,9 @@
 function create(old, msg, code, status, details) {
     /** @type AuthError */
     //@ts-ignore
-    var err = new Error(old);
-    err.client_message = msg;
+    let err = new Error(msg);
+    err.message = msg;
+    err._old_message = old;
     err.code = code;
     err.status = status;
     if (details) {