Get the current record ID using JavaScript in D365 CE – Vblogs

var formCustomizations = {
    getRecordDetail: function (executionContext) {
        var formContext = executionContext.getFormContext();
        var recordId = formContext.data.entity.getId();
        var entityName = formContext.data.entity.getEntityName();
        alert(`Record GUID: ${recordId} and Entity Name: ${entityName}`);
    }
}