Adding a condition fails when Contact/CreatedBy is involved
When trying to add certain conditions which involve Contact/CreatedBy, the page is not displayed and the following PHP warning happens:
"PHP message: PHP Warning: Cannot modify header information - headers already sent by (output started at [...]/civicrm/ext/org.civicoop.civirules/CRM/CivirulesConditions/Contact/CreatedBy.php:1) in [...]/plugins/civicrm/civicrm/CRM/Utils/System/Base.php on line 945"
This is caused by 4 unneeded spaces in the beginning of the mentioned file, which is the actual output.