Inspired by kellym/smartquotesjs and using its regexes, a quote (and ellipsis) smaritifier that transcends tags. I use it as a bookmarklet. (I mostly gave it this name so it would be before "LICENSE" alphabetically.)

Heartquotes.js

(function(transform, root) {
  root = root || document.body;
  
  var TEXT_NODE = Element.TEXT_NODE, ELEMENT_NODE = Element.ELEMENT_NODE;
  
  var contents = '', nodes = [];
  
  function replace(regex, string, fakeLookbehind) {
    var any = false;
    do {
      var match = regex.exec(contents);
      if(!match || !match[0]) {
        return any;
      }
      any = true;
      var length = match[0].length, index = match.index;
      if(fakeLookbehind) {
        length -= match[1].length;
        index += match[1].length;
      }
      var point = 0, i = 0, len = nodes.length, node;
      for(; i < len; ++i) {
        node = nodes[i];
        var np = point + node.nodeValue.length;
        if(np > index) {
          break;
        }
        point = np;
      }
      if(i >= len) {
        throw Error("Match seems to be outside of the region!");
      }
      contents = contents.substr(0, index)
               + string
               + contents.substr(index + length);
      index -= point;
      if(node.nodeValue.length < index + length) {
        var amt = node.nodeValue.length - index;
        node.nodeValue = node.nodeValue.substr(0, index) + string;
        for(var l = length - amt; l > 0 && ++i < len;) {
          var n = nodes[i];
          if(n.nodeValue.length < l) {
            l -= n.nodeValue.length;
            n.nodeValue = '';
          } else {
            n.nodeValue = n.nodeValue.substr(l);
          }
        }
      } else {
        node.nodeValue = node.nodeValue.substr(0, index)
                       + string
                       + node.nodeValue.substr(index + length);
      }
      regex.lastIndex += string.length - length;
    } while(regex.global);
  }
  
  function flush() {
    transform(replace, contents);
    
    contents = '';
    nodes.length = 0;
  }
  
  function element(el) {
    var display = window.getComputedStyle(el).getPropertyValue('display');
    if(display === 'none') {
      return;
    } else if(display === 'block') {
      flush();
    }
    
    if(/^(code|pre|script|style)$/i.test(el.nodeName)) {
      if(display !== 'block') {
        contents += 'x';
        nodes.push({nodeValue: 'x'});
      }
      return;
    }
    
    var children = el.childNodes;
    for(var i = 0, len = children.length; i < len; ++i) {
      var child = children[i];
      if(child.nodeType === TEXT_NODE) {
        contents += child.nodeValue;
        nodes.push(child);
      } else if(child.nodeType === ELEMENT_NODE) {
        element(child);
      }
    }
    
    if(display === 'block') {
      flush();
    }
  }
  
  element(root);
  flush();
})(function(replace) {
  // thanks to Kelly Martin for writing the brilliant code these were adapted from.
  replace(/'''/g, '\u2034');                                                  // triple prime
  replace(/(\W|^)"(?=\S)/g, '\u201c', true);                                  // beginning "
  replace(/(\u201c[^"]*)"(?=[^"]*$|[^\u201c"]*\u201c)/g, '\u201d', true);     // ending "
  replace(/([^0-9])"/g, '\u201d', true);                                      // remaining " at end of word
  replace(/''/g, '\u2033');                                                   // double prime
  replace(/(\W|^)'(?=\S)/g, '\u2018', true);                                  // beginning '
  replace(/([a-z])'(?=[a-z])/ig, '\u2019', true);                             // conjunction's possession
  replace(/((\u2018[^']*)|[a-z])'(?=[^0-9]|$)/ig, '\u2019', true);            // ending '
  replace(/(\u2018)(?=([0-9]{2}[^\u2019]*)(\u2018([^0-9]|$)|$|\u2019[a-z]))/ig, '\u2019'); // abbrev. years like '93
  replace(/(\B|^)\u2018(?=([^\u2019]*\u2019\b)*([^\u2019\u2018]*\W[\u2019\u2018]\b|[^\u2019\u2018]*$))/ig, '\u2019', true); // backwards apostrophe
  replace(/'/g, '\u2032');
  replace(/\.\.\./g, '\u2026');
});

LICENSE

The MIT License (MIT)

Copyright (c) 2016 Permutator.
Includes portions which are copyright (c) 2013 Kelly Martin under the same
license.

Permission is hereby granted, free of charge, to any person obtaining a copy of
this software and associated documentation files (the "Software"), to deal in
the Software without restriction, including without limitation the rights to
use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of
the Software, and to permit persons to whom the Software is furnished to do so,
subject to the following conditions:

The above copyright notice and this permission notice shall be included in all
copies or substantial portions of the Software.

THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS
FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR
COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER
IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.