wiki logo missing from front page

I built a plinth package from this tag: https://github.com/jvalleroy/Plinth/tree/v0.13.0test (same as my update-setup.py branch)

And I built a virtualbox image including that package. After installing ikiwiki and creating a wiki, the front page shows a missing icon for the wiki. From the page source it is looking for /plinth/static/theme/icons/glyphicon-edit.png (should be ikiwiki.png instead). I don't know the cause of this issue yet.