Not able to add second event handler in UI Builder: When I try to add more than one event handler on a button component, it disappears, when I click Add.Issue When a second event handler is attempted to be added to a button component in UI Builder, it will not save, and disappears, once the save button is clicked.SymptomsThe following steps describe an "example" of what leads up to the issue: Open UI builderGo to the desired workspace and open the record page.Select a component on this page that is a viewport, lets call it "Master Entity" viewportSelect and edit "Master Entity" viewportOpen the "master_entity_form"Select "Button_1"Select the "Events" tabNotice there is already an existing event handler added to "Button_1"Select "Add handler" to attempt to add a second event handler to "Button_1"Select from the drop down menu "Open or close modal dialog" for "Add handler"Click ContinueSelect "Duplicates Modal"Click AddNotice the event handler disappearsReleaseAll releasesCauseFor reverence, please see Community article: https://www.servicenow.com/community/sysadmin-forum/event-handler-changes-not-saving-in-ui-builder/m-p/2901570#M12793 As detailed by this article, the cause is that the Event mapping array is empty, and this is seen when you look at the Composition section of the sys_ux_macroponent, it is empty. To determine if this is the root cause, do the following: Go to the sys_metadata table in list view and filter for the scope of the application, and filter on the most recently updated macroponents (eg. filter on application name contains <scope> and Update name=macroponent)Find the most recent updated macroponent records and open them.Check and see if any of the Composition sections have empty eventMapping sections like this: { "definitions": { "id": "MACROPONENT_VIEWPORT_HEADLESS", "type": "MACROPONENT_VIEWPORT_HEADLESS" } "element.abel": "Viewport 1", "elementid": "viewport_1"; "eventMappings": [ <---- This section is empty!! ], ResolutionThe eventMapping in the Composition section cannot be empty. The best resolution is to do the following: Go to another instance that does not have this issue, and copy the entire Composition section from the macroponent, and replace the entire Composition section of the broken macroponent, in the instance that has the issue.Re-test per the steps above, and you should now be able to add the second event handler.