Ok.. I think your both confused and I'm confused myself...
Shippo means CTRL + Tab shortcut.. which you can use to change between different conversations when the Tabbed Chats feature is enabled.
Here's a preview of tabbed chats.
ooniell, you means ALT + Tab, which changes windows, which you can use to change different conversations if you don't have the tabbed chats feature enabled (which isn't Plus! related)
ooniell, what is it you are requesting? A different shortcut other than CTRL + Tab to change tabbed chat windows? Sorry, I'm a little confused.
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