Duplicate element-id "rellinks" generated when html_theme_option 'show_relbars' is 'true'

[hofmandl1]

The HTML snippet for the nav-element with the "previous document" / "next document" links is emitted twice in the same page's html (above and below the content) resulting in a duplicate id "rellinks". I have not observed any broken behaviour, but a html sanity checker made me notice this.