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Aha! Thanks.
I expected each folder to open a new tab as it opened. Evidently not :)
So you Command + T then open a folder in that tab then do the same again for a second folder. Hmm.
 
You can also click on view > Show tab bar.

That will show you a small area at the top right to just click to open a new tab.

[edit] great minds and all that :)

[/edit]
 
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