differentiate op's "special" tabs (widget, mail,
etc)

widgets, transfer, bookmark manager, notes, etc
some websites could use favicons that closely resemble any of opera's
"special" 
tabs.

possibly the special tabs could have visual differentiation? outline border?
inverse 
background/border? 
perhaps an option allowing grouping or sorting the special tabs within tabbar? 
or convert the buttons (for special-tabs) in toolbars to activator/toggles?

this is just a little lazy partial brainstorming.. :-)

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