Question

Can I query (in a jQuery sense) the DOM elements – not just text nodes – completely selected by the mouse?

Answer 1

This will get you all the elements that are completely selected:

var currentSelection = window.getSelection();
var firstRangeInSelection = currentSelection.getRangeAt(0);
var commonAncestor = firstRangeInSelection.commonAncestorContainer;

var nodesInSelection = $(commonAncestor).find("*").filter(function() {
                           return currentSelection.containsNode(this, false);
                       });

For more info on DOM Selections, check out this page.