Hey all!
We recently upgraded to WHMCS 8.6, and all is well except for a few issues.
Occasionally a ticket will throw an error when opening it, this ticket could be brand-new or days old with many replies in it:
TypeError: in_array(): Argument #2 ($haystack) must be of type array, null given in /var/www/html/ponyboy/supporttickets.php:0
Stack trace:
#0 /var/www/html/ponyboy/supporttickets.php(0): in_array()
#1 {main}\]
I can still access the ticket via the WHMCS mobile app, it's just the browser that complains.