diff --git a/docs.it4i/js/show-internals.js b/docs.it4i/js/show-internals.js
deleted file mode 100644
index bcc4fd2f8f48c186fa470db19e17e15733cdfef3..0000000000000000000000000000000000000000
--- a/docs.it4i/js/show-internals.js
+++ /dev/null
@@ -1,203 +0,0 @@
-var EVENTS = [
-	// HTMLMediaElement
-	"loadstart",
-	"progress",
-	"suspend",
-	"abort",
-	"error",
-	"emptied",
-	"stalled",
-	"loadedmetadata",
-	"loadeddata",
-	"canplay",
-	"canplaythrough",
-	"playing",
-	"waiting",
-	"seeking",
-	"seeked",
-	"ended",
-	"durationchange",
-	"timeupdate",
-	"play",
-	"pause",
-	"ratechange",
-	"resize",
-	"volumechange",
-
-	// HTMLTTYPlayerElement
-	"titlechange"
-];
-
-var PROPERTIES = [
-	// HTMLMediaElement
-	["error", null],
-	["src", "string"],
-	["currentSrc", null],
-	["crossOrigin", "string", 10],
-	["networkState", null],
-	["preload", "string", 8],
-	["buffered", null],
-	["readyState", null],
-	["seeking", null],
-	["currentTime", "number", "15ex"],
-	["duration", null],
-	["paused", null],
-	["defaultPlaybackRate", "number", "15ex"],
-	["playbackRate", "number", "15ex"],
-	["played", null],
-	["seekable", null],
-	["ended", null],
-	["autoplay", "boolean"],
-	["loop", "boolean"],
-	["mediaGroup", "string", 10],
-	["controller", "unsupported"],
-	["controls", "boolean"],
-	["volume", "number", "15ex"],
-	["muted", "boolean"],
-	["defaultMuted", "boolean"],
-	["audioTracks", null],
-	["videoTracks", null],
-	["textTracks", null],
-
-	// HTMLTTYPlayerElement
-	["defaultTitle", "string"],
-	["title", "string"],
-	["cols", null],
-	["rows", null],
-	["poster", "string"]
-];
-
-function makePropertyWidget(player, name, widgetType, extra) {
-	switch (widgetType) {
-		case "unsupported":
-		case null:
-			var span = document.createElement("span");
-			return [span, function() { span.textContent = player[name]; }];
-		case "string":
-			var input = document.createElement("input");
-			input.type = "text";
-			if (extra) {
-				input.size = extra;
-			}
-			input.onchange = function() {
-				player[name] = input.value;
-			};
-			return [input, function() { if (document.activeElement !== input) input.value = player[name]; }];
-		case "number":
-			var input = document.createElement("input");
-			input.type = "number";
-			input.step = "any";
-			if (extra) {
-				input.style.width = extra;
-			}
-			input.onchange = function() {
-				player[name] = +input.value;
-			};
-			return [input, function() { if (document.activeElement !== input) input.value = player[name]; }];
-		case "boolean":
-			var input = document.createElement("input");
-			input.type = "checkbox";
-			input.onclick = function() {
-				player[name] = input.checked;
-			};
-			return [input, function() { if (document.activeElement !== input) input.checked = player[name]; }];
-	}
-}
-
-function makePropertiesTable(player) {
-	var updaters = [];
-	var table = document.createElement("table");
-	table.className = "internals media-properties";
-	var caption = document.createElement("caption");
-	caption.textContent = "Media properties";
-	table.appendChild(caption);
-	var tbody = document.createElement("tbody");
-	table.appendChild(tbody);
-	var tr;
-	for (var i = 0; i < PROPERTIES.length; i++) {
-		if (i % 3 == 0) {
-			tr = document.createElement("tr");
-			tbody.appendChild(tr);
-		}
-		var name = PROPERTIES[i][0];
-		var th = document.createElement("th");
-		th.textContent = name;
-		var td = document.createElement("td");
-		if (name in player) {
-			td.className = "true";
-			var widget = makePropertyWidget(player, name, PROPERTIES[i][1], PROPERTIES[i][2]);
-			td.appendChild(widget[0]);
-			updaters.push(widget[1]);
-		} else {
-			td.className = "false";
-		}
-		tr.appendChild(th);
-		tr.appendChild(td);
-	}
-
-	setInterval(function() {
-		for (var i = 0; i < updaters.length; i++) {
-			updaters[i]();
-		}
-	}, 250);
-
-	return table;
-}
-
-function makeEventsTable(player) {
-	var table = document.createElement("table");
-	table.className = "internals media-events";
-	var caption = document.createElement("caption");
-	caption.textContent = "Media events";
-	table.appendChild(caption);
-	var tbody = document.createElement("tbody");
-	table.appendChild(tbody);
-	var tr;
-	for (var i = 0; i < EVENTS.length; i++) {
-		if (i % 5 == 0) {
-			tr = document.createElement("tr");
-			tbody.appendChild(tr);
-		}
-		var name = EVENTS[i];
-		var th = document.createElement("th");
-		th.textContent = name;
-		var td = makeEventCounter(player, name);
-		tr.appendChild(th);
-		tr.appendChild(td);
-	}
-	return table;
-}
-
-function makeEventCounter(element, name) {
-	var td = document.createElement("td");
-	var count = 0;
-	td.textContent = "0";
-	td.className = "false";
-	element.addEventListener(name, function() {
-		count++;
-		td.textContent = count;
-		td.className = "true";
-	});
-	return td;
-}
-
-addEventListener("DOMContentLoaded", function() {
-	var label = document.createElement("label");
-	label.id = "show-internals";
-	label.title = "Add with each <tty-player> element tables showing the event counts and property values.";
-	var toggle = document.createElement("input");
-	toggle.type = "checkbox";
-	toggle.onclick = function() {
-		document.body.classList[toggle.checked ? "add" : "remove"]("show-internals");
-	};
-	label.appendChild(toggle);
-	label.appendChild(document.createTextNode(" Show internals"));
-	document.querySelector("header h1").appendChild(label);
-
-	Array.prototype.forEach.call(document.querySelectorAll("tty-player"), function(player) {
-		var eventsTable = makeEventsTable(player);
-		var propertiesTable = makePropertiesTable(player);
-		player.parentNode.insertBefore(propertiesTable, player.nextSibling);
-		player.parentNode.insertBefore(eventsTable, player.nextSibling);
-	});
-});