The following issues were found:

1. Useless constants
   • WIDGET_HAT_EVENTACTIONMCMDS
   • WIDGET_HAT_EVENTACTIONMSGS
2. Useless profile keys
   • web.tr_events.hats.hat_eventactionmsgs.state
   • web.tr_events.hats.hat_eventactionmcmds.state

Originally, the above constants were used to save the state, whether each of the tables Message actions and Command actions on Event details page is collapsed, to user profile. After -ZBXNEXT-4447- these tables are gone, but constants are not. They can be safely removed from defines.inc.php and tr_events.php.

WIDGET_HAT_EVENTACK and web.tr_events.hats.hat_eventack.state were used for table Acknowledgements. Now they are used for table Actions. Please consider renaming them to WIDGET_HAT_EVENTACTIONS and web.tr_events.hats.hat_eventactions.state or similar.