Is there a way to add a button to a sublist like

items

? I tried things like this but they don't work

var sublist = context.form.getSublist({
      id: 'item'
    });
    sublist.addButton({
      id: 'custpage_example_button',
      label: 'Example',
    });

I don't think you can add to a native sublist like that. You could try adding a custom inline html field in the UI. Then use something like a client script to add a button html to the column. Or something along these lines.

Yeah, I was wondering if I can add some kind of button on top of the sublist instead of creating one per line. But it seems the unique way