diff --git a/js/interface/dialog.js b/js/interface/dialog.js
index f749d3b3..672e6e51 100644
--- a/js/interface/dialog.js
+++ b/js/interface/dialog.js
@@ -814,6 +814,7 @@ window.ShapelessDialog = class ShapelessDialog extends Dialog {
 		super(id, options);
 
 		if (options.build) this.build = options.build;
+		if (options.onClose) this.onClose = options.onClose;
 	}
 	close(button, event) {
 		if (button == this.confirmIndex && typeof this.onConfirm == 'function') {
@@ -824,6 +825,10 @@ window.ShapelessDialog = class ShapelessDialog extends Dialog {
 			let result = this.onCancel(event);
 			if (result === false) return;
 		}
+		if (typeof this.onClose == 'function') {
+			let result = this.onClose(event);
+			if (result === false) return;
+		}
 		this.hide();
 	}
 	show() {
@@ -839,7 +844,7 @@ window.ShapelessDialog = class ShapelessDialog extends Dialog {
 		}
 	}
 	delete() {
-		this.object.remove()
+		if (this.object) this.object.remove()
 	}
 }
 
@@ -939,7 +944,7 @@ window.MessageBox = class MessageBox extends Dialog {
 		}
 	}
 	delete() {
-		this.object.remove()
+		if (this.object) this.object.remove()
 	}
 }