Version: (using KDE KDE 3.0.3) OS: Linux Tried this only on Mandrake 9.0 supplied KDE. When selecting empty space in Konsole (or even text) and dragging the mouse upwards, it leaves a trail of weird characters. This occurs with both anti aliasing turned on and off. In order to get rid of the trails, move another application to completely block the Konsole window and then refocux on Konsole window. Also, selecting the space after it already has those weird effects sometimes clears part of them. This is not limited to Konsole, although it is best seen in it especially with black on yellow scheme. I've experienced same problem with nedit (try mono fonts - some seem to not trigger it). Also, apparently as a side effect, some font letters seem to have missing pixels after this. This is very annoying.
If it also occurs with nedit it's not a KDE or Konsole problem. Strange graphic hardware, Intel perhaps (known for broken driver)?
I am using Geforce4 Ti4600 with generic Geforce4 driver that came with Mandrake 9.0. Switching to generic Geforce3 driver or Geforce2 DDR driver made no difference. Changing resolutions and color modes (originally 1280x1024 at 24bit) did not help either. This problem appears to manifest a lot more often if you select specific fonts. It looks like an X server problem because running nedit in Gnome appears to cause the same problem if you select mono fonts, but there are no problems with Gnome terminal under Gnome or KDE.