diff --git a/api/js/etemplate/Layout/Et2Split/Et2Split.ts b/api/js/etemplate/Layout/Et2Split/Et2Split.ts
index d373913910..c77f79fd18 100644
--- a/api/js/etemplate/Layout/Et2Split/Et2Split.ts
+++ b/api/js/etemplate/Layout/Et2Split/Et2Split.ts
@@ -321,7 +321,10 @@ export class Et2Split extends Et2Widget(SlotMixin(SlSplitPanel))
 			// Tell widgets that manually resize about it
 			this.iterateOver(function(_widget)
 			{
-				_widget.resize();
+				if (typeof _widget.resize === 'function')
+				{
+					_widget.resize();
+				}
 			}, self, et2_IResizeable);
 		}.bind(this), 100);
 	}
diff --git a/api/js/etemplate/et2_extension_nextmatch.ts b/api/js/etemplate/et2_extension_nextmatch.ts
index 9220be523c..5ccebc0cb5 100644
--- a/api/js/etemplate/et2_extension_nextmatch.ts
+++ b/api/js/etemplate/et2_extension_nextmatch.ts
@@ -1731,7 +1731,10 @@ export class et2_nextmatch extends et2_DOMWidget implements et2_IResizeable, et2
 			// Allow column widgets a chance to resize
 			self.iterateOver(function(widget)
 			{
-				widget.resize();
+				if (typeof widget.resize === 'function')
+				{
+					widget.resize();
+				}
 			}, self, et2_IResizeable);
 		};
 
@@ -2191,7 +2194,10 @@ export class et2_nextmatch extends et2_DOMWidget implements et2_IResizeable, et2
 		// Allow column widgets a chance to resize
 		this.iterateOver(function(widget)
 		{
-			widget.resize();
+			if (typeof widget.resize === 'function')
+			{
+				widget.resize();
+			}
 		}, this, et2_IResizeable);
 	}
 
diff --git a/api/js/etemplate/et2_widget_portlet.ts b/api/js/etemplate/et2_widget_portlet.ts
index 9436ef3a5e..f41d059154 100644
--- a/api/js/etemplate/et2_widget_portlet.ts
+++ b/api/js/etemplate/et2_widget_portlet.ts
@@ -150,7 +150,12 @@ export class et2_portlet extends et2_valueWidget
 						self
 					);
 					// Tell children
-					self.iterateOver(function(widget) {widget.resize();},null,et2_IResizeable);
+					self.iterateOver(function(widget) {
+						if (typeof widget.resize === 'function')
+						{
+							widget.resize();
+						}
+					},null,et2_IResizeable);
 				}
 			});
 		this.header = jQuery(document.createElement("div"))
@@ -330,7 +335,12 @@ export class et2_portlet extends et2_valueWidget
 				{
 					// Tell children
 					try {
-						this.iterateOver(function(widget) {widget.resize();},null,et2_IResizeable);
+						this.iterateOver(function(widget) {
+							if (typeof widget.resize === 'function')
+							{
+								widget.resize();
+							}
+						},null,et2_IResizeable);
 					} catch (e) {
 						// Something went wrong, but do not stop
 						egw.debug('warn',e,this);
@@ -429,5 +439,4 @@ export class et2_portlet extends et2_valueWidget
 		this.div.css('height','');
 	}
 }
-et2_register_widget(et2_portlet, ["portlet"]);
-
+et2_register_widget(et2_portlet, ["portlet"]);
\ No newline at end of file
diff --git a/api/js/etemplate/etemplate2.ts b/api/js/etemplate/etemplate2.ts
index dc4b1b95d7..2b2a6183a8 100644
--- a/api/js/etemplate/etemplate2.ts
+++ b/api/js/etemplate/etemplate2.ts
@@ -276,7 +276,10 @@ export class etemplate2
 					{
 						self._widgetContainer.iterateOver(function(_widget)
 						{
-							_widget.resize(excess_height);
+							if (typeof _widget.resize === 'function')
+							{
+								_widget.resize(excess_height);
+							}
 						}, self, et2_IResizeable);
 					}
 				}
diff --git a/calendar/js/et2_widget_timegrid.ts b/calendar/js/et2_widget_timegrid.ts
index 20ee03912a..2b653060f4 100644
--- a/calendar/js/et2_widget_timegrid.ts
+++ b/calendar/js/et2_widget_timegrid.ts
@@ -943,8 +943,10 @@ export class et2_calendar_timegrid extends et2_calendar_view implements et2_IDet
 		if(this.rowHeight != old_height)
 		{
 			this.iterateOver(function(child) {
-				if(child === this) return;
-				child.resize();
+				if (child !== this && typeof child.resize === 'function')
+				{
+					child.resize();
+				}
 			},this, et2_IResizeable);
 		}