Since Xray 6.4.0 users are able to receive Xray notifications such as Product Announcements, Release Updates, and others.
Checking notifications
Notifications will be only visible at "Xray Reports," "Xray Test Repository," "Xray Test Plan Board," and "Automated Steps Library."
Enabling and Disabling notifications
"Xray Notification Settings" page is accessible from your user profile menu.
You can turn notifications "on" and "off" globally (first toggle in the image below) or select Upgrade/Information notification types (the second and third toggles in the image below).
If you would like to disable notifications your instance, you can turn off this feature for all users from the Jira Administration > Apps > Xray > Miscellaneous. Learn more at Miscellaneous.