Wrapping content between two shapes fail in Microsoft Edge

[anderseide]

When using the technique described in the "Alice in Wonderland" example (https://www.html5rocks.com/en/tutorials/shapes/getting-started/#toc-inside-shape among other), this fails in Microsoft Edge and Firefox.

Works in IE 11 and Chrome

Experience Firefox and Microsoft Edge

Experience IE 11 and Chrome 57

Example code (from the demo set)
simple-shape-outsides.html.txt

[foobarbecue]

I'm working on it over here but it's tricky. https://github.com/foobarbecue/css-shapes-polyfill/tree/double-side