A bit better error handling

coordinates_extension.py

@@ -207,6 +207,7 @@ class CoordinatesExtension(inkex.EffectExtension):
 
     def effect(self) -> None:
         images = self.svg.selection.get(IImage)
+        pilimages = list()
         for elem in images:
             xlink = elem.get("xlink:href")
             if xlink is not None and xlink[:5] == "data:":
@@ -221,15 +222,30 @@ class CoordinatesExtension(inkex.EffectExtension):
                 else:
                     imgdata = base64.b64decode(data)
                     pilimage = Image.open(io.BytesIO(imgdata))
+                    pilimages.append(pilimage)
 
-        if not pilimage:
+        if len(pilimages) == 0:
             self.window.message_box("Could not find image in selection")
             self.window.show_all()
             self.window.destroy()
         else:
-            self.window.add_image(pilimage, mimetype)
-            self.window.show_all()
-        Gtk.main()
+            breakout = False
+            for pilimage in pilimages:
+                try:
+                    self.window.add_image(pilimage, mimetype)
+                    breakout = True
+                except gi.repository.GLib.GError as e:
+                    self.window.message_box(
+                        "Could not load image type: {}, error was: {}".format(
+                            mimetype, e))
+                    breakout = False
+                if breakout:
+                    break
+            if breakout:
+                self.window.show_all()
+                Gtk.main()
+            else:
+                self.window.destroy()
 
 
 if __name__ == '__main__':