The dynamically created sidebar in the online documentation defines some link targets that can clash with targets in the actual page content.

E.g. on http://doc.qt.io/qt-5/qtcore-index.html , clicking "Getting Started" in the Contents section won't bring you to the section of the same name in the page - instead it will jump to the "Getting Started" sidebar left. The same goes for the "Reference" link:

http://doc.qt.io/qt-5/qtcore-index.html#getting-started

http://doc.qt.io/qt-5/qtcore-index.html#reference