Say that a custom user or role name regex needs Enterprise

pages/database-management/authentication-and-authorization/users.mdx

@@ -52,6 +52,13 @@ If you want to create a username that includes a space character, you must set
 the `--auth-user-or-role-name-regex` flag to include spaces. For example,
 `--auth-user-or-role-name-regex=[a-zA-Z0-9_.+\-@ ]+`.
 
+A custom value for this flag requires a [Memgraph Enterprise
+license](/database-management/enabling-memgraph-enterprise). Without one,
+Memgraph starts, but every `CREATE USER` query fails with the `Custom user/role
+regex is a Memgraph Enterprise feature` error, even for names the default
+pattern allows. In Memgraph Community, remove the flag or set it back to its
+default, `[a-zA-Z0-9_.+-@]+`.
+
 If the user should authenticate themselves on each session, i.e. provide their
 password on each session, the part within the brackets is mandatory. Otherwise,
 the password is set to `null`, and the user will be allowed to log-in using

pages/database-management/configuration.mdx

@@ -397,7 +397,7 @@ auth module authentication and authorization mechanisms used by Memgraph.
 | `--auth-module-timeout-ms`         | Specifies the maximum time that Memgraph will wait for a response from the external auth module.                                                                                                                                                                                  |
 | `--auth-password-permit-null`      | Can be set to false to disable null passwords.                                                                                                                                                                                                                                    |
 | `--auth-password-strength-regex`   | The regular expression that should be used to match the entire entered password to ensure its strength. The syntax for regular expressions is derived from a [modified version of the ECMAScript regular expression grammar](https://en.cppreference.com/w/cpp/regex/ecmascript). |
-| `--auth-user-or-role-name-regex`   | Set to the regular expression that each user or role name must fulfill. The syntax for regular expressions is derived from a [modified version of the ECMAScript regular expression grammar](https://en.cppreference.com/w/cpp/regex/ecmascript).                                 |
+| `--auth-user-or-role-name-regex`   | Set to the regular expression that each user or role name must fulfill. The syntax for regular expressions is derived from a [modified version of the ECMAScript regular expression grammar](https://en.cppreference.com/w/cpp/regex/ecmascript). The default is `[a-zA-Z0-9_.+-@]+`. A custom value requires a [Memgraph Enterprise license](/database-management/enabling-memgraph-enterprise). |
 
 
 ### Bolt

pages/database-management/enabling-memgraph-enterprise.mdx

@@ -218,6 +218,12 @@ passwords are replaced with **** to prevent their exposure in the logs. This
 approach ensures that even if logs are accessed by unauthorized individuals,
 they won’t be able to retrieve the actual passwords.
 
+### Custom user and role names
+
+With Memgraph Enterprise, you can allow other characters, such as spaces, in
+user and role names by setting the `--auth-user-or-role-name-regex` flag. See
+the [Users page](/database-management/authentication-and-authorization/users#administer-users).
+
 ## Logging and monitoring 
 
 ### Audit log