# Summary xfwm4 killed with SIGTRAP from glib in clientSendConfigureNotify client.c:699 calling XSendEvent(). # Context * Xubuntu 20.04, up-to-date, no heavy configuration tweaking or special software installed, no PPA (initially). Machine seems sane, no mysterious crashes. # Path followed * xfwm4 crashes (and is automatically restarted) about once a week. (By the way, after xfwm4 restart, all windows get moved to the right and bottom by the thickness of left and top decorations in the style used.) * I logged in on /dev/tty1 and there started gdb which ran fxwm4 --replace. * Installed Ubuntu PPA for dbgsym packages and xfwm4-dbgsym. * This time, crash happened after machine (a laptop) woke from suspend-to-ram. Other crash conditions exist. * X session was reachable but could not focus any window, so I guessed xfwm4 was frozen. * Indeed on /dev/tty1 gdb was available. Captured stack trace and core dump. * Stack trace is attached: [gdb_xfwm4_02_bt.txt](/uploads/9b3ea5ed6a07d915d7dc974f5afbbfdf/gdb_xfwm4_02_bt.txt) * Core dump available, just ask.