Steps to reproduce:

• Press F1 on a member of QString, e.g. QString::number in the source
• The Side-by-side help opens and either it shows the help for QString::number or scrolls to end of QString documentation
• If it scrolled to end, it helps to press ESC once and F1 again and it shows the correct help
• Now close the side help by pressing ESC twice, and choose another QString member, e.g. QString::toInt(): the help scrolls to end of page.
• This can be repeated forever

Note: As long as the side help stays open, everything works fine.