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Opera launches latest browser beta: Tab stacking nice feature

Tab grouping is not strange to Firefox users. It has been available through Tab Kit plug-in since 2007 with even more features: collapse or expand tab groups, move tabs from one group to another, put the tab bar on ANY edge of the window - with a nice extra feature when it is vertical: nesting - and many more options. It is a "must have" plug-in for Firefox users.

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