First I thought it was a WordPress issue so I logged it at the WordPress support forum as 221285. Today I was asked for reproduction after disabling the theme and then all plugins in WordPress trac ticket 9107.
In the former topic I noted my results: Google Analytics for WordPress causes the duplicate text. I then noticed version 2.9 of the plugin and tried that one but this didn't resolve the issue. It may have to do with internal links or something like that?