App crashes upon deployment on the backend system (!!!)

Hello experts,

I have an app that is working just fine with SAP Web IDE (personal edition). I deployed the application in my back-end system and, when I started testing and to my big surprise, after I tried to save an erroneous entry (wanted to see if error messages are coming as expected), I got the error "Cannot read property 'getParent' of undefined". "Undefined" refers to a message popover that I use in my base controller. Exception doesn't occur within my code but within MessagePopover-dbg.js (snapshot attached below, line in error 1209).

SAPUI5 version on Web IDE: 1.44.12

SAPUI5 version on back-end system: 1.44.23

Base controller code, along with the routine that calls the popover attached below. Under other circumstances, I would normally issue a note to SAP but, since I'm new in SAPUI5, I'm not 100% sure that I'm not missing anything. Any ideas?

/********** Base controller ***********/


sap.ui.define([
		"sap/ui/core/mvc/Controller",
		"sap/ui/model/json/JSONModel",
		"sap/m/MessagePopover",
		"sap/m/MessagePopoverItem"
	], function (Controller, JSONModel, MessagePopover, MessagePopoverItem) {
		"use strict";


		var oMessageTemplate = new MessagePopoverItem({
			type: "{type}",
			title: "{title}",
			description: "{description}"
		});	
		var oMessagePopover = new MessagePopover({
			id: "actionEditMessagePopover", 
			items: {
				path: '/',
				template: oMessageTemplate
			}
		});	


		var msgModel = new JSONModel("testModel");
				
		return Controller.extend("kristal.apps.agreements.controller.BaseController", {
			/**
			 * Convenience method for accessing the router.
			 * @public
			 * @returns {sap.ui.core.routing.Router} the router for this component
			 */
			getRouter : function () {
				return sap.ui.core.UIComponent.getRouterFor(this);
			},


			/**
			 * Convenience method for getting the view model by name.
			 * @public
			 * @param {string} [sName] the model name
			 * @returns {sap.ui.model.Model} the model instance
			 */
			getModel : function (sName) {
				return this.getView().getModel(sName);
			},


			/**
			 * Convenience method for setting the view model.
			 * @public
			 * @param {sap.ui.model.Model} oModel the model instance
			 * @param {string} sName the model name
			 * @returns {sap.ui.mvc.View} the view instance
			 */
			setModel : function (oModel, sName) {
				return this.getView().setModel(oModel, sName);
			},


			/**
			 * Getter for the resource bundle.
			 * @public
			 * @returns {sap.ui.model.resource.ResourceModel} the resourceModel of the component
			 */
			getResourceBundle : function () {
				return this.getOwnerComponent().getModel("i18n").getResourceBundle();
			},


			/**
			 * Event handler when the share by E-Mail button has been clicked
			 * @public
			 */
			onShareEmailPress : function () {
				var oViewModel = (this.getModel("objectView") || this.getModel("worklistView"));
				sap.m.URLHelper.triggerEmail(
					null,
					oViewModel.getProperty("/shareSendEmailSubject"),
					oViewModel.getProperty("/shareSendEmailMessage")
				);
			},
			_renderSAPMessages: function(response, sStart, oControl) {
				// Extract messages
				// Catch logic works when we have multiple lines, re-initializes
				// next line proccessing
				this.messageArray = [];
				var message;
				var start = sStart + 14;
				var resultString = response.substring(start);
				var messageStart = resultString.indexOf("code") - 1;
				var messageEnd = resultString.indexOf("details") - 2;
				while (messageEnd > 0) {
					message = "{" + resultString.substring(messageStart, messageEnd) + "}";
					message = message.replace("severity\":", "type\": ");
					//message = message.replace("message\":", "description\": ");
					message = message.replace("message\":", "subtitle\": ");
					message = message.replace("code\":", "title\": ");
					message = message.replace("error", "Error");	
					message = message.replace("warning", "Warning");
					message = message.replace("Z666Z", "\",\"description\": \"");
					try {
						message = JSON.parse(message);
						message.title = message.title + " " + message.subtitle;
						this.messageArray.push(message);
						var streamEnd = resultString.indexOf("}]}") - 1;
						messageEnd += 1;
						if (streamEnd < messageEnd) {
						//	messageEnd = 0;
							start = resultString.indexOf("sap-message: {") + 14;
							if (start > 0) {
								resultString = resultString.substring(start);
								messageStart = resultString.indexOf("code") - 1;
								messageEnd = resultString.indexOf("details") - 2;
							} else {
								messageEnd = 0;
							}						
						} else {
							resultString = resultString.substring(messageEnd);
							messageStart = resultString.indexOf("code") - 1;
							if (messageStart > 0) {
								messageEnd = resultString.indexOf("}");
							}
							else {
								break;
							}
						}
					}
					catch(err) {
						start = resultString.indexOf("sap-message: {") + 14;
						if (start > 0) {
							resultString = resultString.substring(start);
							messageStart = resultString.indexOf("code") - 1;
							messageEnd = resultString.indexOf("details") - 2;
						} else {
							messageEnd = 0;
						}
					}					
				}
	
				msgModel.setData(this.messageArray);
	
				oMessagePopover.setModel(msgModel);			
	
				if (this.messageArray.length > 0) {
					oMessagePopover.openBy(oControl);
				}
			},
			_checkIfBatchRequestSucceeded: function(oEvent) {
				var oParams = oEvent.getParameters();
				var aRequests = oEvent.getParameters().requests;
				var oRequest;
				if (oEvent.getParameters().response.responseText.indexOf("sap-message: {") !== null) {
					return true;	
				}
				else
				{
					if (oParams.success) {
						if (aRequests) {
							for (var i = 0; i < aRequests.length; i++) {
								oRequest = oEvent.getParameters().requests[i];
								if (!oRequest.success) {
									return false;
								}
							}
						}
						return true;
					} else {
						return false;
					}
				}
			},
			_checkMessagePopoverState: function() {
				if (oMessagePopover.isOpen()) {
					oMessagePopover.close();
				}
			}
		});


	}
);

/*********************** call to Popover ************************/


			onHeaderSave: function() {


				var that = this;
				var oModelUpdateDeferred = jQuery.Deferred();
				var bCheckSuccess;
				var oModel = this.getView().getModel();


				this._checkMessagePopoverState();
				// abort if the  model has not been changed
				if (!oModel.hasPendingChanges()) {
					MessageBox.information(
						this.getResourceBundle().getText("noChangesMessage"), {
							id: "noChangesInfoMessageBox",
							styleClass: that.getOwnerComponent().getContentDensityClass()
						}
					);
					return;
				}			


				oModel.attachEventOnce("batchRequestCompleted", function(oEvent) {
				// Get control to display message list next to 
				var oControl = sap.ui.getCore().byId("application-agreements-display-component---object--objectAgreementHeaderForm");
					if (that._checkIfBatchRequestSucceeded(oEvent)) {
						that._renderSAPMessages(oEvent.getParameters().response.responseText,
						oEvent.getParameters().response.responseText.indexOf("sap-message: {"),
						oControl);
						if (oEvent.getParameters().response.responseText.indexOf("sap-message: {") < 0) {
							bCheckSuccess = true;	
						} else {
							bCheckSuccess = false;	
						}	
 						oModelUpdateDeferred.resolve();	
					}
				});
					
				oModel.submitChanges({
					success: function(oData, sResponse) {
					},
					error: function(oError) {
						jQuery.sap.log.error("oData Failure", oError);
					}
				});	
				var readyToGo = function() {
					if (bCheckSuccess === true) {
						this.getView().byId("saveHeaderButton").setVisible(false);
						this.getView().byId("cancelHeaderButton").setVisible(false);
						this.getView().byId("editHeaderButton").setVisible(true);
						this._bindHeaderReadOnly();
					}
				};
				jQuery.when(oModelUpdateDeferred).done().then( jQuery.proxy(readyToGo, this) );				
			}