Opera released the beta version of Opera 11 browser which supports Extensions and Tab stacking and many more features and improvements.
Features
Tab stacking - tab stacking lets you drag one tab over another to create a group.
Extensions support
Visual mouse gestures - This allows new users to discover the speed and power that mouse gestures offer.
A safer address field
Better performance
Enhanced HTML5 support
Extended auto-update
Plug-ins only on demand
Faster installation
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