When the plasmoid is removed from the panel, the channels are not closed. The channels are still registered on dbus, and MC probably thinks that they are still handled, therefore the chat-ui cannot handle it, and messages and notifications are not displayed (they are still logged by the logger though) When you call the destroy method on the channel (i did that using d-feet), the next message starts a new channel and therefore is displayed correctly.
Git commit 642b552331ed5ef63064efe671ac6a214f2bf755 by David Edmundson. Committed on 18/03/2013 at 02:54. Pushed by davidedmundson into branch 'master'. Fix memory leak and close all text channels on exit REVIEW: 109559 M +1 -0 KTp/Declarative/conversation.cpp M +1 -0 KTp/Declarative/conversations-model.cpp http://commits.kde.org/telepathy-common-internals/642b552331ed5ef63064efe671ac6a214f2bf755