diff --git a/copyparty/web/md.css b/copyparty/web/md.css
index 392deb99..c4924526 100644
--- a/copyparty/web/md.css
+++ b/copyparty/web/md.css
@@ -83,6 +83,7 @@ h3 {
 h1 a, h3 a, h5 a,
 h2 a, h4 a, h6 a {
 	color: inherit;
+	display: block;
 	background: none;
 	border: none;
 	padding: 0;
@@ -239,7 +240,7 @@ blink {
 	}
 	#mn.undocked {
         position: fixed;
-		padding: 1.2em 0 1em 1em;
+		padding: 1.7em 0 1.5em 1em;
 		box-shadow: 0 0 .5em rgba(0, 0, 0, 0.3);
 		background: #f7f7f7;
 	}
diff --git a/copyparty/web/md.js b/copyparty/web/md.js
index 5bc9b81f..4e85f4a0 100644
--- a/copyparty/web/md.js
+++ b/copyparty/web/md.js
@@ -6,10 +6,30 @@ var dom_pre = document.getElementById('mp');
 var dom_src = document.getElementById('mt');
 var dom_navtgl = document.getElementById('navtoggle');
 
+
+// chrome 49 needs this
+var chromedbg = function () { console.log(arguments); }
+
+// null-logger
+var dbg = function () { };
+
+// replace dbg with the real deal here or in the console:
+// dbg = chromedbg
+// dbg = console.log
+
+
 function hesc(txt) {
     return txt.replace(/&/g, "&amp;").replace(/</g, "&lt;").replace(/>/g, "&gt;");
 }
 
+
+function cls(dom, name, add) {
+    var re = new RegExp('(^| )' + name + '( |$)');
+    var lst = (dom.getAttribute('class') + '').replace(re, "$1$2").replace(/  /, "");
+    dom.setAttribute('class', lst + (add ? ' ' + name : ''));
+}
+
+
 // add navbar
 (function () {
     var n = document.location + '';
@@ -28,17 +48,105 @@ function hesc(txt) {
     dom_nav.innerHTML = nav.join('');
 })();
 
+
+// faster than replacing the entire html (chrome 1.8x, firefox 1.6x)
+function copydom(src, dst, lv) {
+    var sc = src.childNodes,
+        dc = dst.childNodes;
+
+    if (sc.length !== dc.length) {
+        dbg("replace L%d (%d/%d) |%d|",
+            lv, sc.length, dc.length, src.innerHTML.length);
+
+        dst.innerHTML = src.innerHTML;
+        return;
+    }
+
+    var rpl = [];
+    for (var a = sc.length - 1; a >= 0; a--) {
+        var st = sc[a].tagName,
+            dt = dc[a].tagName;
+
+        if (st !== dt) {
+            dbg("replace L%d (%d/%d) type %s/%s", lv, a, sc.length, st, dt);
+            rpl.push(a);
+            continue;
+        }
+
+        var sa = sc[a].attributes || [],
+            da = dc[a].attributes || [];
+
+        if (sa.length !== da.length) {
+            dbg("replace L%d (%d/%d) attr# %d/%d",
+                lv, a, sc.length, sa.length, da.length);
+
+            rpl.push(a);
+            continue;
+        }
+
+        var dirty = false;
+        for (var b = sa.length - 1; b >= 0; b--) {
+            var name = sa[b].name,
+                sv = sa[b].value,
+                dv = dc[a].getAttribute(name);
+
+            if (name == "data-ln" && sv !== dv) {
+                dc[a].setAttribute(name, sv);
+                continue;
+            }
+
+            if (sv !== dv) {
+                dbg("replace L%d (%d/%d) attr %s [%s] [%s]",
+                    lv, a, sc.length, name, sv, dv);
+
+                dirty = true;
+                break;
+            }
+        }
+        if (dirty)
+            rpl.push(a);
+    }
+
+    // TODO pure guessing
+    if (rpl.length > sc.length / 3) {
+        dbg("replace L%d fully, %s (%d/%d) |%d|",
+            lv, rpl.length, sc.length, src.innerHTML.length);
+
+        dst.innerHTML = src.innerHTML;
+        return;
+    }
+
+    // repl is reversed; build top-down
+    var nbytes = 0;
+    for (var a = rpl.length - 1; a >= 0; a--) {
+        var html = sc[rpl[a]].outerHTML;
+        dc[rpl[a]].outerHTML = html;
+        nbytes += html.length;
+    }
+    if (nbytes > 0)
+        dbg("replaced %d bytes L%d", nbytes, lv);
+
+    for (var a = 0; a < sc.length; a++)
+        copydom(sc[a], dc[a], lv + 1);
+
+    if (src.innerHTML !== dst.innerHTML) {
+        dbg("setting %d bytes L%d", src.innerHTML.length, lv);
+        dst.innerHTML = src.innerHTML;
+    }
+}
+
+
 function convert_markdown(md_text) {
     marked.setOptions({
         //headerPrefix: 'h-',
         breaks: true,
         gfm: true
     });
-    var html = marked(md_text);
-    dom_pre.innerHTML = html;
+    var md_html = marked(md_text);
+    var md_dom = new DOMParser().parseFromString(md_html, "text/html").body;
 
     // todo-lists (should probably be a marked extension)
-    var nodes = dom_pre.getElementsByTagName('input');
+    var nodes = md_dom.getElementsByTagName('input');
     for (var a = nodes.length - 1; a >= 0; a--) {
         var dom_box = nodes[a];
         if (dom_box.getAttribute('type') !== 'checkbox')
@@ -58,9 +166,10 @@ function convert_markdown(md_text) {
             html.substr(html.indexOf('>') + 1);
     }
 
-    var manip_nodes = dom_pre.getElementsByTagName('*');
-    for (var a = manip_nodes.length - 1; a >= 0; a--) {
-        var el = manip_nodes[a];
+    // separate <code> for each line in <pre>
+    var nodes = md_dom.getElementsByTagName('pre');
+    for (var a = nodes.length - 1; a >= 0; a--) {
+        var el = nodes[a];
 
         var is_precode =
             el.tagName == 'PRE' &&
@@ -77,18 +186,45 @@ function convert_markdown(md_text) {
 
         el.innerHTML = lines.join('');
     }
+
+    // self-link headers
+    var id_seen = {},
+        dyn = md_dom.getElementsByTagName('*');
+
+    nodes = [];
+    for (var a = 0, aa = dyn.length; a < aa; a++)
+        if (/^[Hh]([1-6])/.exec(dyn[a].tagName) !== null)
+            nodes.push(dyn[a]);
+
+    for (var a = 0; a < nodes.length; a++) {
+        el = nodes[a];
+        var id = el.getAttribute('id'),
+            orig_id = id;
+
+        if (id_seen[id]) {
+            for (var n = 1; n < 4096; n++) {
+                id = orig_id + '-' + n;
+                if (!id_seen[id])
+                    break;
+            }
+            el.setAttribute('id', id);
+        }
+        id_seen[id] = 1;
+        el.innerHTML = '<a href="#' + id + '">' + el.innerHTML + '</a>';
+    }
+
+    copydom(md_dom, dom_pre, 0);
 }
 
+
 function init_toc() {
     var loader = document.getElementById('ml');
     loader.parentNode.removeChild(loader);
 
     var anchors = [];  // list of toc entries, complex objects
     var anchor = null; // current toc node
-    var id_seen = {};  // taken IDs
     var html = [];     // generated toc html
     var lv = 0;        // current indentation level in the toc html
-    var re = new RegExp('^[Hh]([1-3])');
 
     var manip_nodes_dyn = dom_pre.getElementsByTagName('*');
     var manip_nodes = [];
@@ -97,7 +233,7 @@ function init_toc() {
 
     for (var a = 0, aa = manip_nodes.length; a < aa; a++) {
         var elm = manip_nodes[a];
-        var m = re.exec(elm.tagName);
+        var m = /^[Hh]([1-6])/.exec(elm.tagName);
         var is_header = m !== null;
         if (is_header) {
             var nlv = m[1];
@@ -110,23 +246,7 @@ function init_toc() {
                 lv--;
             }
 
-            var orig_id = elm.getAttribute('id');
-            var id = orig_id;
-            if (id_seen[id]) {
-                for (var n = 1; n < 4096; n++) {
-                    id = orig_id + '-' + n;
-                    if (!id_seen[id])
-                        break;
-                }
-                elm.setAttribute('id', id);
-            }
-            id_seen[id] = 1;
-
-            var ahref = '<a href="#' + id + '">' +
-                elm.innerHTML + '</a>';
-
-            html.push('<li>' + ahref + '</li>');
-            elm.innerHTML = ahref;
+            html.push('<li>' + elm.innerHTML + '</li>');
 
             if (anchor != null)
                 anchors.push(anchor);
diff --git a/copyparty/web/md2.css b/copyparty/web/md2.css
index 0cd77226..80f02123 100644
--- a/copyparty/web/md2.css
+++ b/copyparty/web/md2.css
@@ -10,6 +10,9 @@
 }
 #mw {
     left: calc(100% - 57em);
+    overflow-y: auto;
+    position: fixed;
+    bottom: 0;
 }
 
 
@@ -21,7 +24,7 @@
 }
 #mw.preview,
 #mtw.editor {
-    z-index: 3;
+    z-index: 5;
 }
 #mtw.single,
 #mw.single {
diff --git a/copyparty/web/md2.js b/copyparty/web/md2.js
index ec9ad888..259850be 100644
--- a/copyparty/web/md2.js
+++ b/copyparty/web/md2.js
@@ -18,11 +18,6 @@ var dom_ref = (function () {
 })();
 
 
-// replace it with the real deal in the console
-var dbg = function () { };
-// dbg = console.log
-
-
 // line->scrollpos maps
 var map_src = [];
 var map_pre = [];
@@ -62,8 +57,10 @@ function genmap(dom) {
 // input handler
 var action_stack = null;
 var nlines = 0;
-(function () {
-    dom_src.oninput = function (e) {
+var draw_md = (function () {
+    var delay = 1;
+    function draw_md() {
+        var t0 = new Date().getTime();
         var src = dom_src.value;
         convert_markdown(src);
 
@@ -77,16 +74,22 @@ var nlines = 0;
         map_src = genmap(dom_ref);
         map_pre = genmap(dom_pre);
 
-        var sb = document.getElementById('save');
-        var cl = (sb.getAttribute('class') + '').replace(/ disabled/, "");
-        if (src == server_md)
-            cl += ' disabled';
+        cls(document.getElementById('save'), 'disabled', src == server_md);
 
-        sb.setAttribute('class', cl);
+        var t1 = new Date().getTime();
+        delay = t1 - t0;
+    }
+
+    var timeout = null;
+    dom_src.oninput = function (e) {
+        clearTimeout(timeout);
+        timeout = setTimeout(draw_md, delay);
         if (action_stack)
             action_stack.push();
-    }
-    dom_src.oninput();
+    };
+
+    draw_md();
+    return draw_md;
 })();
 
 
@@ -296,7 +299,7 @@ function save_chk() {
 
     last_modified = this.lastmod;
     server_md = this.txt;
-    dom_src.oninput();
+    draw_md();
 
     var ok = document.createElement('div');
     ok.setAttribute('style', 'font-size:6em;font-family:serif;font-weight:bold;color:#cf6;background:#444;border-radius:.3em;padding:.6em 0;position:fixed;top:30%;left:calc(50% - 2em);width:4em;text-align:center;z-index:9001;transition:opacity 0.2s ease-in-out;opacity:1');
@@ -366,7 +369,7 @@ function setsel(s) {
     dom_src.value = [s.pre, s.sel, s.post].join('');
     dom_src.setSelectionRange(s.car, s.cdr);
     try {
-        dom_src.oninput();
+        draw_md();
     }
     catch (ex) { }
 }
@@ -426,7 +429,7 @@ function md_home(shift) {
 function md_newline() {
     var s = linebounds(true),
         ln = s.md.substring(s.n1, s.n2),
-        m = /^[ \t#>+-]*(\* )?([0-9]+\. +)?/.exec(ln);
+        m = /^[ \t>+-]*(\* )?([0-9]+\. +)?/.exec(ln);
 
     s.pre = s.md.substring(0, s.car) + '\n' + m[0];
     s.sel = '';
@@ -561,7 +564,7 @@ action_stack = (function () {
         dom_src.value = ref;
         dom_src.setSelectionRange(state.cursor, state.cursor);
         ignore = true; // all browsers
-        dom_src.oninput();
+        draw_md();
         return true;
     }
 
@@ -577,6 +580,10 @@ action_stack = (function () {
     }
 
     function undo() {
+        if (redos.length == 0) {
+            clearTimeout(sched_timer);
+            push();
+        }
         return apply(undos, redos);
     }