Disable chart title editing AG-Grid

I'm currently trying out AG-Grid and I can't seem to disable title editing in the charts.

Have a look at the plnkr and double click on the title of each chart and see what I mean.

I'm thinking that it should be something along the lines of this:

    title: {
            fontWeight: 'normal',
            editable: false,
            }

but i cant seem to get it to work.

Any suggestions?

Thanks