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We added the possibility to use the front-end "New Administrator Email" field to compute a site ID.

• {new_admin_email} : This is the new administrator email address
• {new_admin_email_left} : This is the left part (before the at @) of the new administrator email address.
• {new_admin_email_left_alnum} : Same as {new_admin_email_left} and remove all special character. Just keep the letter, digits and the '-' character.
• {new_admin_email_right} : This is the domain name of the logged joomla new administrator email address. This is the right part after the at @ character.
• {new_admin_email_right-1} to {new_admin_email_right-n} : This extract the part present in the domain name from right to left using the dot (.) as separator.

We also autorise to have a site ID that is an email address

• {site_id_left} : This is the left part (before the at @) of the site identifier.
• {site_id_left_alnum} : Same as {site_id_left} and remove all special character. Just keep the letter, digits and the '-' character.
• {site_id_right} : This is the part after the at @ character of the site identifier.
• {site_id_right-1} to {site_id_right-n} : This extract the part present in the domain name from right to left using the dot (.) as separator.