LDAP Client Missing Escape Method
From Joomla! Documentation
The LDAP authentication plugin tries to call a non-existing `escape` method on the Joomla\Ldap\LdapClient class.
This pertains only to Joomla! version(s): 3.8.0
What is the cause
A file was not correctly updated in the 3.8.0 release.
How to fix
Replace the file at libraries/vendor/joomla/ldap/src/LdapClient.php with the version found at https://github.com/joomla-framework/ldap/blob/1.2.0/src/LdapClient.php