Purpose

Some organizations don't like their employees playing games which comes with the JIRA Credits page. For example, in JIRA 6.4.X , the Space Invader like game was available : 

Solution

Hide the JIRA Credits button using JavaScript :

1. Navigate to the Announcement banner page
2. Enter this snippet on the field
   

<style>
a#view_credits {display:none} /* Removes View Credits button */
</style>

The JIRA Credits button is now no longer visible.