How can i prevent close ticket view after assign to agent?

Agent open ticket
Click to "Assign"
Select another agent and click to button "Assign"
Ticket view closed, but i want to write comment under ticket before 🙁 .
And i don't see in source code JavaScript which did it.

osticket_agent
Dirty solution.
In file include\staff\ticket-view.inc.php change remove strings about 145-152 with, data-redirect="tickets.php"