Inspired by [a meta question](http://meta.stackexchange.com/questions/242220/full-resolution-option-for-embedded-pictures), here's a script that makes every image in a post also open itself at full size in a new window/tab when clicked.

It will ignore any images already manually linked.

Please suggest any improvements, or better yet [submit a pull request on GitHub](https://github.com/Elusive138/SEImageExpander).

The current version can be found at and installed from [here](https://github.com/Elusive138/SEImageExpander/raw/master/SEImageExpander.user.js).

    // ==UserScript==
    // @name          SEImageExpander
    // @namespace     http://vulpin.com/
    // @description	  Let people click on images to view the full size
    // @match         *://*.askubuntu.com/*
    // @match         *://*.mathoverflow.net/*
    // @match         *://*.onstartups.com/*
    // @match         *://*.serverfault.com/*
    // @match         *://*.stackapps.com/*
    // @match         *://*.stackexchange.com/*
    // @match         *://*.stackoverflow.com/*
    // @match         *://*.superuser.com/*
    // @version       1.0.3
    // @grant         none
    // ==/UserScript==
    
    (function() {
    var Program = {
        main: function() {
            window.removeEventListener('load', mainEventListener, false);
            
            var observer = new MutationObserver(function(mutations, observer) {
                // y'know what? MutationObserver sucks.
                // it doesn't give every modified node, just the top of a tree of modified nodes
                mutations.forEach(function(mutation) {
                    Array.prototype.forEach.call(mutation.addedNodes, Program.processImgDescendants);
                });
            });
            
            observer.observe(document, {
                subtree: true,
                childList: true
            });
            
            Program.processImgDescendants(document);
        },
        
        processImgDescendants: function(node) {
            if (!node) {
                return;
            }
            
            var imgNodes = node.querySelectorAll('.post-text img');
            
            Array.prototype.forEach.call(imgNodes, function(imgNode) {
                Program.processNode(imgNode);
            });
        },
        
        processNode: function(node) {
            if (node.tagName.toUpperCase() !== 'IMG') {
                return;
            }
            
            // walk up the tree until we reach the main post div, we don't care what's beyond that
            var parent = node;
            while (!parent.classList.contains('post-text')) {
                // if this image is already within a link, don't touch it
                if (parent.tagName.toUpperCase() === 'A') {
                    return;
                }
                
                parent = parent.parentNode;
                
                // have we made it all the way to the top? we're not in a post!
                if (parent === null) {
                    return;
                }
            }
            
            // ok, now we know the node is an unlinked image within a post
            var link = document.createElement('a');
            link.href = node.src;
            link.target = '_blank';
            node.parentNode.replaceChild(link, node);
            link.appendChild(node);
        }
    };
    
    var mainEventListener = Program.main.bind(Program);
    
    window.addEventListener('load', mainEventListener, false);
    })();