Firefox has always had the option of forcing a link that tries to open in a new window to open in a new tab. Reader J writes in with a good reason to take it a step further. J configures Firefox to force links that try to open in new windows to open tabs in the background, instead. J explains:

Google Reader seems pretty neat, but it's always bugged me that using the "v" key to view a link opens that link in a new tab. I usually like to browse all feed items, open interesting links in the background, and then view the opened links [all at once].

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