The first two are, I assume, because a desktop system has no power management system. The third one is what prompted this report. The last one (the X complaint) should also be considered. # krusader Object::connect: No such signal org::freedesktop::UPower::DeviceAdded(QString) Object::connect: No such signal org::freedesktop::UPower::DeviceRemoved(QString) krusader(3285)/kdeui (kdelibs) KXMLGUIClient::~KXMLGUIClient: 0x227d980 deleted without having been removed from the factory first. This will leak standalone popupmenus and could lead to crashes. X Error: BadWindow (invalid Window parameter) 3 Major opcode: 20 (X_GetProperty) Resource id: 0x30000e2 Reproducible: Always Steps to Reproduce: 1. Start krusader from a command line 2. Work a bit 3. exit krusader Actual Results: See details Expected Results: No error or warning messages I flagged his as "minor" because it is. And, as far as I could see, there was no need of a "work around" since krusader seemed to work properly. The presence of these warnings does seem, to me, to suggest somewhat sloppy coding, or (more likely) changes in upstream standards which -- since they don't affect functionality -- could be "deferred."
sometimes i also met this issue. when i close a krusader window, krusader alert a window and say "X Error: BadWindow (invalid Window parameter) 3 Major opcode: 20 (X_GetProperty)". in my situation it's not about the way to lauch krusader because i started it from lancelot launcher. if i restart krusader this alert window may never popped up again.
This version of Krusader is unmantained, please update to 2.7.2 and reopen the bug if the issue is still present.