Selecting text through different CSS-Region flows
This text contains a footnote as a nested region what is diplayed below the article. (1)
(1) This is a footnote. Footnotes can be quite long and go over several lines. This footnote
is nested inside the text above and displayed here with the help of css-regions. If you start selecting
text from this article until somewhere in the footnote and then click somewhere, the selection should be cleared.