Having Problems Rated 4 out of 5 stars

I loved and used Diigo for a long time, and appreciated their benefits over Delicious, but having too many problems now. Reading here it seems I'm not alone. I can't really complain given I only used free version and I wish them well. Does anyone know of a good alternative?

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This review is for a previous version of the add-on (5.1.0.32.1-signed).