Theme faces in org-tree-slide

[fbergroth]

The header in org-tree-slide looks a bit off, being black and having lines interspersed.

You can test it with this doc:

#+TITLE: Test

* Header 1
** Header 2
*** Header 3

and M-x org-tree-slide-mode, and navigate slides with C-> and C-<.

[cpaulik]

I'm not sure this applies anymore

If that does not look right then please re-open