Firegesture script to logically open link or duplicate tab in background next to current tab, meaning it will be selected if current tab is closed or minimized. Requires tab deque extension.

firegesture-logically-open-link-or-duplicate-tab-next-to-current.js

// if the gesture started from a link, open link in new tab
var linkURL = FireGestures.getLinkURL(FireGestures.sourceNode);
if (linkURL) {
    gTabDeque.moveTabToSecondPlaceInDeque(gBrowser.loadOneTab(linkURL, {inBackground: true}));
    return;
}

// else duplicate tab
gTabDeque.moveTabToSecondPlaceInDeque(gBrowser.loadOneTab(gBrowser.currentURI.spec, {inBackground: true}));