further googling answered my question. The upgrade disabled anti-aliasing (??). To re-enable in KDE you have to select the anti-alias check box in control center->fonts AND you have to enter the configuration sub-menu since anti-aliasing is turned off for fonts between 8 and 15pt. by default. So re-enable anti-aliasing AND further enable it for ALL point sizes. As always, obvious in hindsight. thanks, OccNoob