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CloseReview for Duplicate Tab Blocker by Sandr0
Rated 4 out of 5 stars
Better be sure to safe or close all your open tabs if you install it the 1st time.
Because it may be (happend at my private-laptop, but not on the work-laptop) that this Add-On removes all Open Tabs.
Once installed it does exaclty what i want!
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