Events builder is the group of selectors on Push Notifications add/edit form, that trigger Notification to some WordPress or 3rd-party plugin action. So, by this form you setup when and who will get the Notification
Selector #1 – Action Environment
Here you choose, what plugin or part of WP core provide actions: Post, Comment, User, Woocomerce, Ultimate Member, ect.
Selector #2 – Type
This selector is active only for some Environments
Here you can choose entity type for action (i.e. Post, Page, Product or ect.).
In Post Environment you can find all custom public entities types provided by WordPress or 3rd-party Plugins
Selector #3 – Action
This selector let you to choose an action (event) on which will Push Notification will be sent. You will see in the list only actions, that are compatible with current Environment
Selector #4 – Target
Here you can choose target (user type) of Push Notification. So only user, who matches this condition will get Push Notifications. (All – all subscribers will get; Current user – user who called action will get, Author – only user who created entity will get, ect.)