This is a nearly perfect solution to something that has driven me crazy for ages. The only problem I've found is that it changes the order in which new tabs appear. Without the extension, if you click on three links to open three new tabs, they appear to the right of the current tab in the order in which you opened them, i.e., from left to right: original, first, second, third. With the extension enabled, they appear in reverse order, i.e., from right to left: original, third, second, first. If this behavior could be turned off, I'd give this extension a 5.
It annoys the hell out of me when ANY application does not work as expected. I have NO problem with "Command" + "Click" for Links/URLs to OPEN in NEW tabs in Safari or Chrome. But, Firefox? Links would open in SAME tab!