Seem to be getting this error when clicking on a notification. (This happened after I upgraded from v3.1.3 to v3.1.4).
Code:
Warning: array_unique() expects parameter 1 to be array, null given in ..../dbtech/usertag/includes/class_cache.php on line 106
Warning: Cannot modify header information - headers already sent by (output started at ..../includes/class_core.php:5703) in ..../includes/functions.php on line 4376