Embed tag inside extended template seems to be broken

Created by: ofabel

The following template is supposed to work: https://twigfiddle.com/l3d401

It seems, that the template path/name resolution is not working as expected (TwingErrorLoader: Unable to find template). Instead of the correct template element.twig the embedded template is resolved to main.twig.

I can provide a working (or in this case not working) example, if required.