With Xfce running, I installed xfcalendar. Then without restarting, I started it and tried to open its preferences. However, I got an error message: "Xfce Settings Manager error: No such plugin 'xfcalendar'." I can start the preferences just fine if I restart xfce-mcs-manager. I imagine this would happen if I installed other components that have a settings manager icon. Possible workaround: is it possible, at the end of installation of such a component, to have xfce-mcs-manager restart without major consequence? I don't know, just an idea....
Andrew, this is a really a WONTFIX. You can manually restart the MCS manager (pkill -USR1 xfce-mcs-manager) if you want, but we won't do this automatically from Makefiles or other installation scripts.
Well, is there another way to call the prefs from xfcalendar? I can understand the icon not showing up in the Settings Manager until you restart the mcs manager, but to have the prefs broken.... At the very least, is this provided in documentation? I'm a little used to the way the Settings Manager 'modules' work, but an Xfce noob may not be....
No, there's no other way to call the xfcalendar prefs. The preferences are a MCS module and therefore need to be loaded into the MCS manager to work. Thats the way the settings work in Xfce 4.0/4.2. This may change for 4.4, but until then you need to restart the MCS manager. The documentation mentions this fact already: "After installing a new package that provides a settings dialog, you can make the manager reread its configuration by sending a SIGUSR1 signal: $ killall -USR1 xfce-mcs-manager"