I have a screen with a sublist. From my client script, I would like to add new line in the Sublist. I think it's possible, right ?

What do you mean by screen with a sublist? A suitelet? What type of sublist is it?

Yes a suitelet a LIST type

I can't remember for sure since I don't really use LIST type, but I think they are static one the page is loaded. Not sure client can add lines to them.

I used the inlineeditor and it worked almost perfectly. It did everything I wanted but it also add the add/update/delete bar, which I don't want