Does exactly what it says it will. Deducted 1 star because when you block a site via the context menu, it blocks the whole web address, which many spam websites avoid by randomising the specific webpage's name or adding random characters in the sub-domain area before the domain name. It would be great to have the option to block a whole *domain* by context menu. You can't edit blocked addresses, so you have to delete the full web address entry and retype just the domain name manually. Also, if you paste something into the manual entry box, it highlights the whole thing so you can't edit just a part of it - Problematic if the website's name is deliberately complicated. If not for these obstacles to ease of use, I'd happily give this 5 stars.