From 5712128ac06c5c85acdc00faea02f9d2fa515107 Mon Sep 17 00:00:00 2001
From: LenAnderson <Anderson.Len@outlook.com>
Date: Sat, 20 Jul 2024 12:16:47 -0400
Subject: [PATCH] improve QR editor performance - only run hljs with syntax
 enabled - only check localStorage once, then rely on the checkbox - run hljs
 on a 30fps loop instead of event-based - use morphdom to update syntax dom
 instead of innerHTML

---
 .../quick-reply/lib/morphdom-esm.js           | 769 ++++++++++++++++++
 .../quick-reply/lib/morphdom.LICENSE.txt      |  21 +
 .../extensions/quick-reply/src/QuickReply.js  |  34 +-
 3 files changed, 819 insertions(+), 5 deletions(-)
 create mode 100644 public/scripts/extensions/quick-reply/lib/morphdom-esm.js
 create mode 100644 public/scripts/extensions/quick-reply/lib/morphdom.LICENSE.txt

diff --git a/public/scripts/extensions/quick-reply/lib/morphdom-esm.js b/public/scripts/extensions/quick-reply/lib/morphdom-esm.js
new file mode 100644
index 000000000..7a13a27fc
--- /dev/null
+++ b/public/scripts/extensions/quick-reply/lib/morphdom-esm.js
@@ -0,0 +1,769 @@
+var DOCUMENT_FRAGMENT_NODE = 11;
+
+function morphAttrs(fromNode, toNode) {
+    var toNodeAttrs = toNode.attributes;
+    var attr;
+    var attrName;
+    var attrNamespaceURI;
+    var attrValue;
+    var fromValue;
+
+    // document-fragments dont have attributes so lets not do anything
+    if (toNode.nodeType === DOCUMENT_FRAGMENT_NODE || fromNode.nodeType === DOCUMENT_FRAGMENT_NODE) {
+      return;
+    }
+
+    // update attributes on original DOM element
+    for (var i = toNodeAttrs.length - 1; i >= 0; i--) {
+        attr = toNodeAttrs[i];
+        attrName = attr.name;
+        attrNamespaceURI = attr.namespaceURI;
+        attrValue = attr.value;
+
+        if (attrNamespaceURI) {
+            attrName = attr.localName || attrName;
+            fromValue = fromNode.getAttributeNS(attrNamespaceURI, attrName);
+
+            if (fromValue !== attrValue) {
+                if (attr.prefix === 'xmlns'){
+                    attrName = attr.name; // It's not allowed to set an attribute with the XMLNS namespace without specifying the `xmlns` prefix
+                }
+                fromNode.setAttributeNS(attrNamespaceURI, attrName, attrValue);
+            }
+        } else {
+            fromValue = fromNode.getAttribute(attrName);
+
+            if (fromValue !== attrValue) {
+                fromNode.setAttribute(attrName, attrValue);
+            }
+        }
+    }
+
+    // Remove any extra attributes found on the original DOM element that
+    // weren't found on the target element.
+    var fromNodeAttrs = fromNode.attributes;
+
+    for (var d = fromNodeAttrs.length - 1; d >= 0; d--) {
+        attr = fromNodeAttrs[d];
+        attrName = attr.name;
+        attrNamespaceURI = attr.namespaceURI;
+
+        if (attrNamespaceURI) {
+            attrName = attr.localName || attrName;
+
+            if (!toNode.hasAttributeNS(attrNamespaceURI, attrName)) {
+                fromNode.removeAttributeNS(attrNamespaceURI, attrName);
+            }
+        } else {
+            if (!toNode.hasAttribute(attrName)) {
+                fromNode.removeAttribute(attrName);
+            }
+        }
+    }
+}
+
+var range; // Create a range object for efficently rendering strings to elements.
+var NS_XHTML = 'http://www.w3.org/1999/xhtml';
+
+var doc = typeof document === 'undefined' ? undefined : document;
+var HAS_TEMPLATE_SUPPORT = !!doc && 'content' in doc.createElement('template');
+var HAS_RANGE_SUPPORT = !!doc && doc.createRange && 'createContextualFragment' in doc.createRange();
+
+function createFragmentFromTemplate(str) {
+    var template = doc.createElement('template');
+    template.innerHTML = str;
+    return template.content.childNodes[0];
+}
+
+function createFragmentFromRange(str) {
+    if (!range) {
+        range = doc.createRange();
+        range.selectNode(doc.body);
+    }
+
+    var fragment = range.createContextualFragment(str);
+    return fragment.childNodes[0];
+}
+
+function createFragmentFromWrap(str) {
+    var fragment = doc.createElement('body');
+    fragment.innerHTML = str;
+    return fragment.childNodes[0];
+}
+
+/**
+ * This is about the same
+ * var html = new DOMParser().parseFromString(str, 'text/html');
+ * return html.body.firstChild;
+ *
+ * @method toElement
+ * @param {String} str
+ */
+function toElement(str) {
+    str = str.trim();
+    if (HAS_TEMPLATE_SUPPORT) {
+      // avoid restrictions on content for things like `<tr><th>Hi</th></tr>` which
+      // createContextualFragment doesn't support
+      // <template> support not available in IE
+      return createFragmentFromTemplate(str);
+    } else if (HAS_RANGE_SUPPORT) {
+      return createFragmentFromRange(str);
+    }
+
+    return createFragmentFromWrap(str);
+}
+
+/**
+ * Returns true if two node's names are the same.
+ *
+ * NOTE: We don't bother checking `namespaceURI` because you will never find two HTML elements with the same
+ *       nodeName and different namespace URIs.
+ *
+ * @param {Element} a
+ * @param {Element} b The target element
+ * @return {boolean}
+ */
+function compareNodeNames(fromEl, toEl) {
+    var fromNodeName = fromEl.nodeName;
+    var toNodeName = toEl.nodeName;
+    var fromCodeStart, toCodeStart;
+
+    if (fromNodeName === toNodeName) {
+        return true;
+    }
+
+    fromCodeStart = fromNodeName.charCodeAt(0);
+    toCodeStart = toNodeName.charCodeAt(0);
+
+    // If the target element is a virtual DOM node or SVG node then we may
+    // need to normalize the tag name before comparing. Normal HTML elements that are
+    // in the "http://www.w3.org/1999/xhtml"
+    // are converted to upper case
+    if (fromCodeStart <= 90 && toCodeStart >= 97) { // from is upper and to is lower
+        return fromNodeName === toNodeName.toUpperCase();
+    } else if (toCodeStart <= 90 && fromCodeStart >= 97) { // to is upper and from is lower
+        return toNodeName === fromNodeName.toUpperCase();
+    } else {
+        return false;
+    }
+}
+
+/**
+ * Create an element, optionally with a known namespace URI.
+ *
+ * @param {string} name the element name, e.g. 'div' or 'svg'
+ * @param {string} [namespaceURI] the element's namespace URI, i.e. the value of
+ * its `xmlns` attribute or its inferred namespace.
+ *
+ * @return {Element}
+ */
+function createElementNS(name, namespaceURI) {
+    return !namespaceURI || namespaceURI === NS_XHTML ?
+        doc.createElement(name) :
+        doc.createElementNS(namespaceURI, name);
+}
+
+/**
+ * Copies the children of one DOM element to another DOM element
+ */
+function moveChildren(fromEl, toEl) {
+    var curChild = fromEl.firstChild;
+    while (curChild) {
+        var nextChild = curChild.nextSibling;
+        toEl.appendChild(curChild);
+        curChild = nextChild;
+    }
+    return toEl;
+}
+
+function syncBooleanAttrProp(fromEl, toEl, name) {
+    if (fromEl[name] !== toEl[name]) {
+        fromEl[name] = toEl[name];
+        if (fromEl[name]) {
+            fromEl.setAttribute(name, '');
+        } else {
+            fromEl.removeAttribute(name);
+        }
+    }
+}
+
+var specialElHandlers = {
+    OPTION: function(fromEl, toEl) {
+        var parentNode = fromEl.parentNode;
+        if (parentNode) {
+            var parentName = parentNode.nodeName.toUpperCase();
+            if (parentName === 'OPTGROUP') {
+                parentNode = parentNode.parentNode;
+                parentName = parentNode && parentNode.nodeName.toUpperCase();
+            }
+            if (parentName === 'SELECT' && !parentNode.hasAttribute('multiple')) {
+                if (fromEl.hasAttribute('selected') && !toEl.selected) {
+                    // Workaround for MS Edge bug where the 'selected' attribute can only be
+                    // removed if set to a non-empty value:
+                    // https://developer.microsoft.com/en-us/microsoft-edge/platform/issues/12087679/
+                    fromEl.setAttribute('selected', 'selected');
+                    fromEl.removeAttribute('selected');
+                }
+                // We have to reset select element's selectedIndex to -1, otherwise setting
+                // fromEl.selected using the syncBooleanAttrProp below has no effect.
+                // The correct selectedIndex will be set in the SELECT special handler below.
+                parentNode.selectedIndex = -1;
+            }
+        }
+        syncBooleanAttrProp(fromEl, toEl, 'selected');
+    },
+    /**
+     * The "value" attribute is special for the <input> element since it sets
+     * the initial value. Changing the "value" attribute without changing the
+     * "value" property will have no effect since it is only used to the set the
+     * initial value.  Similar for the "checked" attribute, and "disabled".
+     */
+    INPUT: function(fromEl, toEl) {
+        syncBooleanAttrProp(fromEl, toEl, 'checked');
+        syncBooleanAttrProp(fromEl, toEl, 'disabled');
+
+        if (fromEl.value !== toEl.value) {
+            fromEl.value = toEl.value;
+        }
+
+        if (!toEl.hasAttribute('value')) {
+            fromEl.removeAttribute('value');
+        }
+    },
+
+    TEXTAREA: function(fromEl, toEl) {
+        var newValue = toEl.value;
+        if (fromEl.value !== newValue) {
+            fromEl.value = newValue;
+        }
+
+        var firstChild = fromEl.firstChild;
+        if (firstChild) {
+            // Needed for IE. Apparently IE sets the placeholder as the
+            // node value and vise versa. This ignores an empty update.
+            var oldValue = firstChild.nodeValue;
+
+            if (oldValue == newValue || (!newValue && oldValue == fromEl.placeholder)) {
+                return;
+            }
+
+            firstChild.nodeValue = newValue;
+        }
+    },
+    SELECT: function(fromEl, toEl) {
+        if (!toEl.hasAttribute('multiple')) {
+            var selectedIndex = -1;
+            var i = 0;
+            // We have to loop through children of fromEl, not toEl since nodes can be moved
+            // from toEl to fromEl directly when morphing.
+            // At the time this special handler is invoked, all children have already been morphed
+            // and appended to / removed from fromEl, so using fromEl here is safe and correct.
+            var curChild = fromEl.firstChild;
+            var optgroup;
+            var nodeName;
+            while(curChild) {
+                nodeName = curChild.nodeName && curChild.nodeName.toUpperCase();
+                if (nodeName === 'OPTGROUP') {
+                    optgroup = curChild;
+                    curChild = optgroup.firstChild;
+                } else {
+                    if (nodeName === 'OPTION') {
+                        if (curChild.hasAttribute('selected')) {
+                            selectedIndex = i;
+                            break;
+                        }
+                        i++;
+                    }
+                    curChild = curChild.nextSibling;
+                    if (!curChild && optgroup) {
+                        curChild = optgroup.nextSibling;
+                        optgroup = null;
+                    }
+                }
+            }
+
+            fromEl.selectedIndex = selectedIndex;
+        }
+    }
+};
+
+var ELEMENT_NODE = 1;
+var DOCUMENT_FRAGMENT_NODE$1 = 11;
+var TEXT_NODE = 3;
+var COMMENT_NODE = 8;
+
+function noop() {}
+
+function defaultGetNodeKey(node) {
+  if (node) {
+    return (node.getAttribute && node.getAttribute('id')) || node.id;
+  }
+}
+
+function morphdomFactory(morphAttrs) {
+
+  return function morphdom(fromNode, toNode, options) {
+    if (!options) {
+      options = {};
+    }
+
+    if (typeof toNode === 'string') {
+      if (fromNode.nodeName === '#document' || fromNode.nodeName === 'HTML' || fromNode.nodeName === 'BODY') {
+        var toNodeHtml = toNode;
+        toNode = doc.createElement('html');
+        toNode.innerHTML = toNodeHtml;
+      } else {
+        toNode = toElement(toNode);
+      }
+    } else if (toNode.nodeType === DOCUMENT_FRAGMENT_NODE$1) {
+      toNode = toNode.firstElementChild;
+    }
+
+    var getNodeKey = options.getNodeKey || defaultGetNodeKey;
+    var onBeforeNodeAdded = options.onBeforeNodeAdded || noop;
+    var onNodeAdded = options.onNodeAdded || noop;
+    var onBeforeElUpdated = options.onBeforeElUpdated || noop;
+    var onElUpdated = options.onElUpdated || noop;
+    var onBeforeNodeDiscarded = options.onBeforeNodeDiscarded || noop;
+    var onNodeDiscarded = options.onNodeDiscarded || noop;
+    var onBeforeElChildrenUpdated = options.onBeforeElChildrenUpdated || noop;
+    var skipFromChildren = options.skipFromChildren || noop;
+    var addChild = options.addChild || function(parent, child){ return parent.appendChild(child); };
+    var childrenOnly = options.childrenOnly === true;
+
+    // This object is used as a lookup to quickly find all keyed elements in the original DOM tree.
+    var fromNodesLookup = Object.create(null);
+    var keyedRemovalList = [];
+
+    function addKeyedRemoval(key) {
+      keyedRemovalList.push(key);
+    }
+
+    function walkDiscardedChildNodes(node, skipKeyedNodes) {
+      if (node.nodeType === ELEMENT_NODE) {
+        var curChild = node.firstChild;
+        while (curChild) {
+
+          var key = undefined;
+
+          if (skipKeyedNodes && (key = getNodeKey(curChild))) {
+            // If we are skipping keyed nodes then we add the key
+            // to a list so that it can be handled at the very end.
+            addKeyedRemoval(key);
+          } else {
+            // Only report the node as discarded if it is not keyed. We do this because
+            // at the end we loop through all keyed elements that were unmatched
+            // and then discard them in one final pass.
+            onNodeDiscarded(curChild);
+            if (curChild.firstChild) {
+              walkDiscardedChildNodes(curChild, skipKeyedNodes);
+            }
+          }
+
+          curChild = curChild.nextSibling;
+        }
+      }
+    }
+
+    /**
+    * Removes a DOM node out of the original DOM
+    *
+    * @param  {Node} node The node to remove
+    * @param  {Node} parentNode The nodes parent
+    * @param  {Boolean} skipKeyedNodes If true then elements with keys will be skipped and not discarded.
+    * @return {undefined}
+    */
+    function removeNode(node, parentNode, skipKeyedNodes) {
+      if (onBeforeNodeDiscarded(node) === false) {
+        return;
+      }
+
+      if (parentNode) {
+        parentNode.removeChild(node);
+      }
+
+      onNodeDiscarded(node);
+      walkDiscardedChildNodes(node, skipKeyedNodes);
+    }
+
+    // // TreeWalker implementation is no faster, but keeping this around in case this changes in the future
+    // function indexTree(root) {
+    //     var treeWalker = document.createTreeWalker(
+    //         root,
+    //         NodeFilter.SHOW_ELEMENT);
+    //
+    //     var el;
+    //     while((el = treeWalker.nextNode())) {
+    //         var key = getNodeKey(el);
+    //         if (key) {
+    //             fromNodesLookup[key] = el;
+    //         }
+    //     }
+    // }
+
+    // // NodeIterator implementation is no faster, but keeping this around in case this changes in the future
+    //
+    // function indexTree(node) {
+    //     var nodeIterator = document.createNodeIterator(node, NodeFilter.SHOW_ELEMENT);
+    //     var el;
+    //     while((el = nodeIterator.nextNode())) {
+    //         var key = getNodeKey(el);
+    //         if (key) {
+    //             fromNodesLookup[key] = el;
+    //         }
+    //     }
+    // }
+
+    function indexTree(node) {
+      if (node.nodeType === ELEMENT_NODE || node.nodeType === DOCUMENT_FRAGMENT_NODE$1) {
+        var curChild = node.firstChild;
+        while (curChild) {
+          var key = getNodeKey(curChild);
+          if (key) {
+            fromNodesLookup[key] = curChild;
+          }
+
+          // Walk recursively
+          indexTree(curChild);
+
+          curChild = curChild.nextSibling;
+        }
+      }
+    }
+
+    indexTree(fromNode);
+
+    function handleNodeAdded(el) {
+      onNodeAdded(el);
+
+      var curChild = el.firstChild;
+      while (curChild) {
+        var nextSibling = curChild.nextSibling;
+
+        var key = getNodeKey(curChild);
+        if (key) {
+          var unmatchedFromEl = fromNodesLookup[key];
+          // if we find a duplicate #id node in cache, replace `el` with cache value
+          // and morph it to the child node.
+          if (unmatchedFromEl && compareNodeNames(curChild, unmatchedFromEl)) {
+            curChild.parentNode.replaceChild(unmatchedFromEl, curChild);
+            morphEl(unmatchedFromEl, curChild);
+          } else {
+            handleNodeAdded(curChild);
+          }
+        } else {
+          // recursively call for curChild and it's children to see if we find something in
+          // fromNodesLookup
+          handleNodeAdded(curChild);
+        }
+
+        curChild = nextSibling;
+      }
+    }
+
+    function cleanupFromEl(fromEl, curFromNodeChild, curFromNodeKey) {
+      // We have processed all of the "to nodes". If curFromNodeChild is
+      // non-null then we still have some from nodes left over that need
+      // to be removed
+      while (curFromNodeChild) {
+        var fromNextSibling = curFromNodeChild.nextSibling;
+        if ((curFromNodeKey = getNodeKey(curFromNodeChild))) {
+          // Since the node is keyed it might be matched up later so we defer
+          // the actual removal to later
+          addKeyedRemoval(curFromNodeKey);
+        } else {
+          // NOTE: we skip nested keyed nodes from being removed since there is
+          //       still a chance they will be matched up later
+          removeNode(curFromNodeChild, fromEl, true /* skip keyed nodes */);
+        }
+        curFromNodeChild = fromNextSibling;
+      }
+    }
+
+    function morphEl(fromEl, toEl, childrenOnly) {
+      var toElKey = getNodeKey(toEl);
+
+      if (toElKey) {
+        // If an element with an ID is being morphed then it will be in the final
+        // DOM so clear it out of the saved elements collection
+        delete fromNodesLookup[toElKey];
+      }
+
+      if (!childrenOnly) {
+        // optional
+        var beforeUpdateResult = onBeforeElUpdated(fromEl, toEl);
+        if (beforeUpdateResult === false) {
+          return;
+        } else if (beforeUpdateResult instanceof HTMLElement) {
+          fromEl = beforeUpdateResult;
+          // reindex the new fromEl in case it's not in the same
+          // tree as the original fromEl
+          // (Phoenix LiveView sometimes returns a cloned tree,
+          //  but keyed lookups would still point to the original tree)
+          indexTree(fromEl);
+        }
+
+        // update attributes on original DOM element first
+        morphAttrs(fromEl, toEl);
+        // optional
+        onElUpdated(fromEl);
+
+        if (onBeforeElChildrenUpdated(fromEl, toEl) === false) {
+          return;
+        }
+      }
+
+      if (fromEl.nodeName !== 'TEXTAREA') {
+        morphChildren(fromEl, toEl);
+      } else {
+        specialElHandlers.TEXTAREA(fromEl, toEl);
+      }
+    }
+
+    function morphChildren(fromEl, toEl) {
+      var skipFrom = skipFromChildren(fromEl, toEl);
+      var curToNodeChild = toEl.firstChild;
+      var curFromNodeChild = fromEl.firstChild;
+      var curToNodeKey;
+      var curFromNodeKey;
+
+      var fromNextSibling;
+      var toNextSibling;
+      var matchingFromEl;
+
+      // walk the children
+      outer: while (curToNodeChild) {
+        toNextSibling = curToNodeChild.nextSibling;
+        curToNodeKey = getNodeKey(curToNodeChild);
+
+        // walk the fromNode children all the way through
+        while (!skipFrom && curFromNodeChild) {
+          fromNextSibling = curFromNodeChild.nextSibling;
+
+          if (curToNodeChild.isSameNode && curToNodeChild.isSameNode(curFromNodeChild)) {
+            curToNodeChild = toNextSibling;
+            curFromNodeChild = fromNextSibling;
+            continue outer;
+          }
+
+          curFromNodeKey = getNodeKey(curFromNodeChild);
+
+          var curFromNodeType = curFromNodeChild.nodeType;
+
+          // this means if the curFromNodeChild doesnt have a match with the curToNodeChild
+          var isCompatible = undefined;
+
+          if (curFromNodeType === curToNodeChild.nodeType) {
+            if (curFromNodeType === ELEMENT_NODE) {
+              // Both nodes being compared are Element nodes
+
+              if (curToNodeKey) {
+                // The target node has a key so we want to match it up with the correct element
+                // in the original DOM tree
+                if (curToNodeKey !== curFromNodeKey) {
+                  // The current element in the original DOM tree does not have a matching key so
+                  // let's check our lookup to see if there is a matching element in the original
+                  // DOM tree
+                  if ((matchingFromEl = fromNodesLookup[curToNodeKey])) {
+                    if (fromNextSibling === matchingFromEl) {
+                      // Special case for single element removals. To avoid removing the original
+                      // DOM node out of the tree (since that can break CSS transitions, etc.),
+                      // we will instead discard the current node and wait until the next
+                      // iteration to properly match up the keyed target element with its matching
+                      // element in the original tree
+                      isCompatible = false;
+                    } else {
+                      // We found a matching keyed element somewhere in the original DOM tree.
+                      // Let's move the original DOM node into the current position and morph
+                      // it.
+
+                      // NOTE: We use insertBefore instead of replaceChild because we want to go through
+                      // the `removeNode()` function for the node that is being discarded so that
+                      // all lifecycle hooks are correctly invoked
+                      fromEl.insertBefore(matchingFromEl, curFromNodeChild);
+
+                      // fromNextSibling = curFromNodeChild.nextSibling;
+
+                      if (curFromNodeKey) {
+                        // Since the node is keyed it might be matched up later so we defer
+                        // the actual removal to later
+                        addKeyedRemoval(curFromNodeKey);
+                      } else {
+                        // NOTE: we skip nested keyed nodes from being removed since there is
+                        //       still a chance they will be matched up later
+                        removeNode(curFromNodeChild, fromEl, true /* skip keyed nodes */);
+                      }
+
+                      curFromNodeChild = matchingFromEl;
+                      curFromNodeKey = getNodeKey(curFromNodeChild);
+                    }
+                  } else {
+                    // The nodes are not compatible since the "to" node has a key and there
+                    // is no matching keyed node in the source tree
+                    isCompatible = false;
+                  }
+                }
+              } else if (curFromNodeKey) {
+                // The original has a key
+                isCompatible = false;
+              }
+
+              isCompatible = isCompatible !== false && compareNodeNames(curFromNodeChild, curToNodeChild);
+              if (isCompatible) {
+                // We found compatible DOM elements so transform
+                // the current "from" node to match the current
+                // target DOM node.
+                // MORPH
+                morphEl(curFromNodeChild, curToNodeChild);
+              }
+
+            } else if (curFromNodeType === TEXT_NODE || curFromNodeType == COMMENT_NODE) {
+              // Both nodes being compared are Text or Comment nodes
+              isCompatible = true;
+              // Simply update nodeValue on the original node to
+              // change the text value
+              if (curFromNodeChild.nodeValue !== curToNodeChild.nodeValue) {
+                curFromNodeChild.nodeValue = curToNodeChild.nodeValue;
+              }
+
+            }
+          }
+
+          if (isCompatible) {
+            // Advance both the "to" child and the "from" child since we found a match
+            // Nothing else to do as we already recursively called morphChildren above
+            curToNodeChild = toNextSibling;
+            curFromNodeChild = fromNextSibling;
+            continue outer;
+          }
+
+          // No compatible match so remove the old node from the DOM and continue trying to find a
+          // match in the original DOM. However, we only do this if the from node is not keyed
+          // since it is possible that a keyed node might match up with a node somewhere else in the
+          // target tree and we don't want to discard it just yet since it still might find a
+          // home in the final DOM tree. After everything is done we will remove any keyed nodes
+          // that didn't find a home
+          if (curFromNodeKey) {
+            // Since the node is keyed it might be matched up later so we defer
+            // the actual removal to later
+            addKeyedRemoval(curFromNodeKey);
+          } else {
+            // NOTE: we skip nested keyed nodes from being removed since there is
+            //       still a chance they will be matched up later
+            removeNode(curFromNodeChild, fromEl, true /* skip keyed nodes */);
+          }
+
+          curFromNodeChild = fromNextSibling;
+        } // END: while(curFromNodeChild) {}
+
+        // If we got this far then we did not find a candidate match for
+        // our "to node" and we exhausted all of the children "from"
+        // nodes. Therefore, we will just append the current "to" node
+        // to the end
+        if (curToNodeKey && (matchingFromEl = fromNodesLookup[curToNodeKey]) && compareNodeNames(matchingFromEl, curToNodeChild)) {
+          // MORPH
+          if(!skipFrom){ addChild(fromEl, matchingFromEl); }
+          morphEl(matchingFromEl, curToNodeChild);
+        } else {
+          var onBeforeNodeAddedResult = onBeforeNodeAdded(curToNodeChild);
+          if (onBeforeNodeAddedResult !== false) {
+            if (onBeforeNodeAddedResult) {
+              curToNodeChild = onBeforeNodeAddedResult;
+            }
+
+            if (curToNodeChild.actualize) {
+              curToNodeChild = curToNodeChild.actualize(fromEl.ownerDocument || doc);
+            }
+            addChild(fromEl, curToNodeChild);
+            handleNodeAdded(curToNodeChild);
+          }
+        }
+
+        curToNodeChild = toNextSibling;
+        curFromNodeChild = fromNextSibling;
+      }
+
+      cleanupFromEl(fromEl, curFromNodeChild, curFromNodeKey);
+
+      var specialElHandler = specialElHandlers[fromEl.nodeName];
+      if (specialElHandler) {
+        specialElHandler(fromEl, toEl);
+      }
+    } // END: morphChildren(...)
+
+    var morphedNode = fromNode;
+    var morphedNodeType = morphedNode.nodeType;
+    var toNodeType = toNode.nodeType;
+
+    if (!childrenOnly) {
+      // Handle the case where we are given two DOM nodes that are not
+      // compatible (e.g. <div> --> <span> or <div> --> TEXT)
+      if (morphedNodeType === ELEMENT_NODE) {
+        if (toNodeType === ELEMENT_NODE) {
+          if (!compareNodeNames(fromNode, toNode)) {
+            onNodeDiscarded(fromNode);
+            morphedNode = moveChildren(fromNode, createElementNS(toNode.nodeName, toNode.namespaceURI));
+          }
+        } else {
+          // Going from an element node to a text node
+          morphedNode = toNode;
+        }
+      } else if (morphedNodeType === TEXT_NODE || morphedNodeType === COMMENT_NODE) { // Text or comment node
+        if (toNodeType === morphedNodeType) {
+          if (morphedNode.nodeValue !== toNode.nodeValue) {
+            morphedNode.nodeValue = toNode.nodeValue;
+          }
+
+          return morphedNode;
+        } else {
+          // Text node to something else
+          morphedNode = toNode;
+        }
+      }
+    }
+
+    if (morphedNode === toNode) {
+      // The "to node" was not compatible with the "from node" so we had to
+      // toss out the "from node" and use the "to node"
+      onNodeDiscarded(fromNode);
+    } else {
+      if (toNode.isSameNode && toNode.isSameNode(morphedNode)) {
+        return;
+      }
+
+      morphEl(morphedNode, toNode, childrenOnly);
+
+      // We now need to loop over any keyed nodes that might need to be
+      // removed. We only do the removal if we know that the keyed node
+      // never found a match. When a keyed node is matched up we remove
+      // it out of fromNodesLookup and we use fromNodesLookup to determine
+      // if a keyed node has been matched up or not
+      if (keyedRemovalList) {
+        for (var i=0, len=keyedRemovalList.length; i<len; i++) {
+          var elToRemove = fromNodesLookup[keyedRemovalList[i]];
+          if (elToRemove) {
+            removeNode(elToRemove, elToRemove.parentNode, false);
+          }
+        }
+      }
+    }
+
+    if (!childrenOnly && morphedNode !== fromNode && fromNode.parentNode) {
+      if (morphedNode.actualize) {
+        morphedNode = morphedNode.actualize(fromNode.ownerDocument || doc);
+      }
+      // If we had to swap out the from node with a new node because the old
+      // node was not compatible with the target node then we need to
+      // replace the old DOM node in the original DOM tree. This is only
+      // possible if the original DOM node was part of a DOM tree which
+      // we know is the case if it has a parent node.
+      fromNode.parentNode.replaceChild(morphedNode, fromNode);
+    }
+
+    return morphedNode;
+  };
+}
+
+var morphdom = morphdomFactory(morphAttrs);
+
+export default morphdom;
diff --git a/public/scripts/extensions/quick-reply/lib/morphdom.LICENSE.txt b/public/scripts/extensions/quick-reply/lib/morphdom.LICENSE.txt
new file mode 100644
index 000000000..d4d35164b
--- /dev/null
+++ b/public/scripts/extensions/quick-reply/lib/morphdom.LICENSE.txt
@@ -0,0 +1,21 @@
+The MIT License (MIT)
+
+Copyright (c) Patrick Steele-Idem <pnidem@gmail.com> (psteeleidem.com)
+
+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.
\ No newline at end of file
diff --git a/public/scripts/extensions/quick-reply/src/QuickReply.js b/public/scripts/extensions/quick-reply/src/QuickReply.js
index d75c1c9de..077f25e0d 100644
--- a/public/scripts/extensions/quick-reply/src/QuickReply.js
+++ b/public/scripts/extensions/quick-reply/src/QuickReply.js
@@ -11,6 +11,7 @@ import { SlashCommandParserError } from '../../../slash-commands/SlashCommandPar
 import { SlashCommandScope } from '../../../slash-commands/SlashCommandScope.js';
 import { debounce, delay, getSortableDelay, showFontAwesomePicker } from '../../../utils.js';
 import { log, quickReplyApi, warn } from '../index.js';
+import morphdom from '../lib/morphdom-esm.js';
 import { QuickReplyContextLink } from './QuickReplyContextLink.js';
 import { QuickReplySet } from './QuickReplySet.js';
 import { ContextMenu } from './ui/ctx/ContextMenu.js';
@@ -537,6 +538,9 @@ export class QuickReply {
             title.addEventListener('input', () => {
                 this.updateTitle(title.value);
             });
+            /**@type {HTMLElement}*/
+            const messageSyntaxInner = dom.querySelector('#qr--modal-messageSyntaxInner');
+            this.editorSyntax = messageSyntaxInner;
             /**@type {HTMLInputElement}*/
             const wrap = dom.querySelector('#qr--modal-wrap');
             wrap.checked = JSON.parse(localStorage.getItem('qr--wrap') ?? 'false');
@@ -581,10 +585,30 @@ export class QuickReply {
             };
             const updateScrollDebounced = updateScroll;
             const updateSyntax = ()=>{
-                messageSyntaxInner.innerHTML = hljs.highlight(`${message.value}${message.value.slice(-1) == '\n' ? ' ' : ''}`, { language:'stscript', ignoreIllegals:true })?.value;
+                if (messageSyntaxInner && syntax.checked) {
+                    morphdom(
+                        messageSyntaxInner,
+                        `<div>${hljs.highlight(`${message.value}${message.value.slice(-1) == '\n' ? ' ' : ''}`, { language:'stscript', ignoreIllegals:true })?.value}</div>`,
+                        { childrenOnly: true },
+                    );
+                }
             };
+            let lastSyntaxUpdate = 0;
+            const fpsTime = 1000 / 30;
+            let lastMessageValue = null;
+            const upsyn = ()=>{
+                const now = Date.now();
+                if (now - lastSyntaxUpdate < fpsTime) return requestAnimationFrame(upsyn);
+                if (!messageSyntaxInner.closest('body')) return;
+                if (lastMessageValue == message.value) return requestAnimationFrame(upsyn);
+                lastSyntaxUpdate = now;
+                lastMessageValue = message.value;
+                updateSyntax();
+                requestAnimationFrame(upsyn);
+            };
+            requestAnimationFrame(()=>upsyn());
             const updateSyntaxEnabled = ()=>{
-                if (JSON.parse(localStorage.getItem('qr--syntax'))) {
+                if (syntax.checked) {
                     dom.querySelector('#qr--modal-messageHolder').classList.remove('qr--noSyntax');
                 } else {
                     dom.querySelector('#qr--modal-messageHolder').classList.add('qr--noSyntax');
@@ -621,11 +645,11 @@ export class QuickReply {
             const message = dom.querySelector('#qr--modal-message');
             this.editorMessage = message;
             message.value = this.message;
+            const updateMessageDebounced = debounce((value)=>this.updateMessage(value));
             message.addEventListener('input', () => {
-                updateSyntax();
-                this.updateMessage(message.value);
+                updateMessageDebounced(message.value);
                 updateScrollDebounced();
-            });
+            }, { passive:true });
             //TODO move tab support for textarea into its own helper(?) and use for both this and .editor_maximize
             message.addEventListener('keydown', async(evt) => {
                 if (this.isExecuting) return;