Hello World Widget tutorial

You are 100% correct. Disregard all the useless typing I added . I have not seen that error in my widget development.

What I can tell you from my experiences is that if the plugin cannot find the template I get an error indicating that it cannot load the template.

I have never built a widget without an UI / template so I am not sure about the fallback. I have also never checked for the container size in a template, I have done the check in the widget code, 1 template for each size.

       if(widgetContext.isEdit()){
              output.append(applyFreemarkerTemplate(widgetContext, size, EDIT_TEMPLATE));
              return output.toString();
          }
          //choose the appropriate render template according to the size
          if (size == ContainerSize.LARGE) {
                 output.append(applyFreemarkerTemplate(widgetContext, size, LARGE_FREEMARKER_TEMPLATE));
            
          } else {
              output.append(applyFreemarkerTemplate(widgetContext, size, SMALL_FREEMARKER_TEMPLATE));
          }

Are you building this with maven? Under the target directory do you see the example/resources/HelloWorldWidget.ftl? Have you debugged into the HelloWorldWidget class, setting a break point on the render method to

see if you template is being loaded?

Also my 2 cents, putting all the logic in a java class is not necessarily wrong, and putting the logic in the template is not necessarily the "right way". I prefer to put as much logic in java and let the template code be as simple as possible. Rendering UI objects, instead of determinig which UI objects to render. Just my 2 cents.