Notice (#1): Requested ID for prefix l not passed in ...\core\kernel\db\db_event_handler.php on line 327
Notice (#2): Parent ID not found (prefix: "l"; sub-prefix: "l-rev") in ...\core\kernel\db\dblist.php on line 1017
After all it seams, that review/comments section was working normally because of the bug, that was fixed.
Prefix "l-rev" (which is used here) is a "l" prefix subitem and therefore requires it's id for data filtering.
To solve this quickly we need to remove filter called "parent_filter" from list based on special used on "reviews_tab" template. Notices still will be displaying in this case.
Other way is to create another review prefix, that won't be a child for any of category item prefixes, as for now.