Traditionally I leave myself in the staff chatroom overnight when I sleep. About 8 hours. This used to always be fine, I'd often have myself online for days at a time.
I have added a couple more rooms that I'm visiting. At least twice now, I come back to my computer and find the spinning busy cursor of doom on my colloquy :( There were 2 total rooms this last time, I think about 200 messages in each one (that I missed)
My prefs, most are default: Smart Transcripts, Drawer List, Synapse, nothing checked on alerts, transcripts page is not logging, set to 1 file session per day, sent history 15, message scrollback 300, auto rejoin, check spelling