[arch-general] KDE panel broken after last upgrade

Hello archers, Last massive KDE upgrade broke my KDE desktop. In particular, after the reboot, the panel was gone. I tried to "Add Panel": Default Panel crashes Plasma Shell; Empty panel works. Then I added one by one the widget I had in my original panel (which was pretty standard). I determined that the "culprit" is task manager: when I try to add this widget, KDE crashes. Any workaround? Thanks, Lorenzo