diff --git a/copyparty/web/browser.css b/copyparty/web/browser.css
index 4930ccee..8953d35e 100644
--- a/copyparty/web/browser.css
+++ b/copyparty/web/browser.css
@@ -579,3 +579,16 @@ input[type="checkbox"]:checked+label {
 	color: #300;
 	background: #fea;
 }
+#op_cfg {
+	max-width: none;
+	margin-right: 1.5em;
+}
+#key_notation>span {
+	display: inline-block;
+	padding: .2em .4em;
+}
+#op_cfg h3 {
+	margin: .8em 0 0 .6em;
+	padding: 0;
+	border-bottom: 1px solid #555;
+}
diff --git a/copyparty/web/browser.html b/copyparty/web/browser.html
index 121869cf..eb58810d 100644
--- a/copyparty/web/browser.html
+++ b/copyparty/web/browser.html
@@ -23,6 +23,7 @@
         <a href="#" data-perm="write" data-dest="mkdir">📂</a>
         <a href="#" data-perm="write" data-dest="new_md">📝</a>
         <a href="#" data-perm="write" data-dest="msg">📟</a>
+        <a href="#" data-dest="cfg">⚙️</a>
     </div>
 
     <div id="op_search" class="opview">
@@ -33,7 +34,13 @@
         {%- endif %}
         <div id="srch_q"></div>
     </div>
+
     {%- include 'upload.html' %}
+
+    <div id="op_cfg" class="opview opbox">
+        <h3>key notation</h3>
+        <div id="key_notation"></div>
+    </div>
     
     <h1 id="path">
         <a href="#" id="entree">🌲</a>
diff --git a/copyparty/web/browser.js b/copyparty/web/browser.js
index 2bc3d661..8625b548 100644
--- a/copyparty/web/browser.js
+++ b/copyparty/web/browser.js
@@ -945,6 +945,7 @@ function autoplay_blocked() {
 		ebi('epi').innerHTML = res.logues ? res.logues[1] || "" : "";
 
 		filecols.set_style();
+		mukey.render();
 		reload_tree();
 		reload_browser();
 	}
@@ -1193,6 +1194,108 @@ var filecols = (function () {
 })();
 
 
+var mukey = (function () {
+	var maps = {
+		"rekobo_alnum": [
+			"1B ", "2B ", "3B ", "4B ", "5B ", "6B ", "7B ", "8B ", "9B ", "10B", "11B", "12B",
+			"1A ", "2A ", "3A ", "4A ", "5A ", "6A ", "7A ", "8A ", "9A ", "10A", "11A", "12A"
+		],
+		"rekobo_classic": [
+			"B  ", "F# ", "Db ", "Ab ", "Eb ", "Bb ", "F  ", "C  ", "G  ", "D  ", "A  ", "E  ",
+			"Abm", "Ebm", "Bbm", "Fm ", "Cm ", "Gm ", "Dm ", "Am ", "Em ", "Bm ", "F#m", "Dbm"
+		],
+		"traktor_musical": [
+			"B  ", "Gb ", "Db ", "Ab ", "Eb ", "Bb ", "F  ", "C  ", "G  ", "D  ", "A  ", "E  ",
+			"Abm", "Ebm", "Bbm", "Fm ", "Cm ", "Gm ", "Dm ", "Am ", "Em ", "Bm ", "Gbm", "Dbm"
+		],
+		"traktor_sharps": [
+			"B  ", "F# ", "C# ", "G# ", "D# ", "A# ", "F  ", "C  ", "G  ", "D  ", "A  ", "E  ",
+			"G#m", "D#m", "A#m", "Fm ", "Cm ", "Gm ", "Dm ", "Am ", "Em ", "Bm ", "F#m", "C#m"
+		],
+		"traktor_open": [
+			"6d ", "7d ", "8d ", "9d ", "10d", "11d", "12d", "1d ", "2d ", "3d ", "4d ", "5d ",
+			"6m ", "7m ", "8m ", "9m ", "10m", "11m", "12m", "1m ", "2m ", "3m ", "4m ", "5m "
+		]
+	};
+	var map = {};
+
+	var html = [];
+	for (var k in maps) {
+		if (!maps.hasOwnProperty(k))
+			continue;
+
+		html.push(
+			'<span><input type="radio" name="keytype" value="' + k + '" id="key_' + k + '">' +
+			'<label for="key_' + k + '">' + k + '</label></span>');
+
+		for (var a = 0; a < 24; a++)
+			maps[k][a] = maps[k][a].trim();
+	}
+	ebi('key_notation').innerHTML = html.join('\n');
+
+	function set_key_notation(e) {
+		ev(e);
+		var notation = this.getAttribute('value');
+		load_notation(notation);
+		render();
+	}
+
+	function load_notation(notation) {
+		swrite("key_notation", notation);
+		map = {};
+		var dst = maps[notation];
+		for (var k in maps)
+			if (k != notation && maps.hasOwnProperty(k))
+				for (var a = 0; a < 24; a++)
+					if (maps[k][a] != dst[a])
+						map[maps[k][a]] = dst[a];
+	}
+
+	function render() {
+		var tds = ebi('files').tHead.getElementsByTagName('th');
+		var i = -1;
+		var min = false;
+		for (var a = 0; a < tds.length; a++) {
+			var spans = tds[a].getElementsByTagName('span');
+			if (spans.length && spans[0].textContent == 'Key') {
+				min = tds[a].getAttribute('class').indexOf('min') !== -1;
+				i = a;
+				break;
+			}
+		}
+
+		if (i == -1)
+			return;
+
+		var rows = ebi('files').tBodies[0].rows;
+
+		if (min)
+			for (var a = 0, aa = rows.length; a < aa; a++) {
+				var v = rows[a].cells[i].getAttribute('html');
+				rows[a].cells[i].setAttribute('html', map[v] || v);
+			}
+		else
+			for (var a = 0, aa = rows.length; a < aa; a++) {
+				var v = rows[a].cells[i].textContent;
+				rows[a].cells[i].textContent = map[v] || v;
+			}
+	}
+
+	var notation = sread("key_notation") || "rekobo_alnum";
+	ebi('key_' + notation).checked = true;
+	load_notation(notation);
+
+	var o = document.querySelectorAll('#key_notation input');
+	for (var a = 0; a < o.length; a++) {
+		o[a].onchange = set_key_notation;
+	}
+
+	return {
+		"render": render
+	};
+})();
+
+
 function ev_row_tgl(e) {
 	ev(e);
 	filecols.toggle(this.parentElement.parentElement.getElementsByTagName('span')[0].textContent);
@@ -1238,3 +1341,4 @@ function reload_browser(not_mp) {
 		up2k.set_fsearch();
 }
 reload_browser(true);
+mukey.render();
diff --git a/copyparty/web/util.js b/copyparty/web/util.js
index 96cd563b..fc08bde6 100644
--- a/copyparty/web/util.js
+++ b/copyparty/web/util.js
@@ -23,6 +23,7 @@ function esc(txt) {
 }
 function vis_exh(msg, url, lineNo, columnNo, error) {
     window.onerror = undefined;
+    window['vis_exh'] = null;
     var html = ['<h1>you hit a bug!</h1><p>please screenshot this error and send me a copy arigathanks gozaimuch (ed/irc.rizon.net or ed#2644)</p><p>',
         esc(String(msg)), '</p><p>', esc(url + ' @' + lineNo + ':' + columnNo), '</p>'];
 
diff --git a/docs/notes.sh b/docs/notes.sh
index 9b3449c3..6f6e6ce2 100644
--- a/docs/notes.sh
+++ b/docs/notes.sh
@@ -11,6 +11,13 @@ gzip -d < .hist/up2k.snap | jq -r '.[].tnam' | while IFS= read -r f; do rm -f --
 gzip -d < .hist/up2k.snap | jq -r '.[].name' | while IFS= read -r f; do wc -c -- "$f" | grep -qiE '^[^0-9a-z]*0' && rm -f -- "$f"; done
 
 
+##
+## detect partial uploads based on file contents
+##  (in case of context loss or old copyparties)
+
+echo; find -type f | while IFS= read -r x; do printf '\033[A\033[36m%s\033[K\033[0m\n' "$x"; tail -c$((1024*1024)) <"$x" | xxd -a | awk 'NR==1&&/^[0: ]+.{16}$/{next} NR==2&&/^\*$/{next} NR==3&&/^[0f]+: [0 ]+65 +.{16}$/{next} {e=1} END {exit e}' || continue; printf '\033[A\033[31msus:\033[33m %s \033[0m\n\n' "$x"; done
+
+
 ##
 ## create a test payload