Route transition doesn't work when working with modal


I’m working with modal using tutorial in ember website.

Only difference is that I’m trying to make the ‘modal’ template have an outlet for another template so make it reusable.

But after I opened modal(rendered modal outlet, exactly), when I try to make transition to another route, It just doesn’t work. but If I write default behavior of renderTemplate in target route. It works again.(I’ve commented it out in my JSBin)

Is it a bug? or did I handled this.render not properly?