The bug appears, if you are editing or looking texts in KDE editors or viewers
(kwrite, kate, krusader internal editor and, probably, all others), and if you
switch on dynamic line breaks. If you set (in KDE system configuration) to
scroll N lines by the mouse wheel, it will scroll N lines of the _file_ you
edit rather than N lines on the editor _screen_. This behavior is very annoying
and inconvenient since scrolling skips entire paragraphs (if each line presents
a paragraph) and the text on the screen moves by large jumps. Note, that the
same problem appears if you scroll the text by moving the slider at the right
edge of the editor window.