This is a known limitation when using Tabbed Chats.
Alternately you can disable tabbed chats.
quote:
Originally posted by Patchou
Thanks for reporting. Unfortunately there's nothing I can do about this. This problem is the result of fixing the more annoying "chat restores automatically when another window is minimised". For those interested in the technical details, this is cause the chat windows are actually disabled when not shown on screen.
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