diff --git a/HISTORY.md b/HISTORY.md
index b9d39178..064406b5 100755
--- a/HISTORY.md
+++ b/HISTORY.md
@@ -8,6 +8,8 @@
 * Cloud: fixed cloud check, thanks, Michael!
 * deduped tools, thanks, Michael!
 * moved translations into subfolder "locale"
+* removed obsolete doc files
+* moved *.js files into subfolder "src" (and edited gui.js to deal with ypr.js)
 
 ## v4.2.1.4
 ### 2018-09-09
diff --git a/snap.html b/snap.html
index e78811c9..5d07758e 100755
--- a/snap.html
+++ b/snap.html
@@ -4,24 +4,24 @@
 		<meta http-equiv="Content-Type" content="text/html; charset=UTF-8">
 		<title>Snap! Build Your Own Blocks 4.2.1.5 - dev -</title>
 		<link rel="shortcut icon" href="favicon.ico">
-		<script type="text/javascript" src="morphic.js?version=2018-06-21"></script>
-		<script type="text/javascript" src="widgets.js?version=2018-06-21"></script>
-		<script type="text/javascript" src="blocks.js?version=2018-09-09"></script>
-		<script type="text/javascript" src="threads.js?version=2018-09-09"></script>
-		<script type="text/javascript" src="objects.js?version=2018-07-06"></script>
-		<script type="text/javascript" src="gui.js?version=2018-10-02"></script>
-		<script type="text/javascript" src="paint.js?version=2018-06-21"></script>
-		<script type="text/javascript" src="lists.js?version=2018-06-21"></script>
-		<script type="text/javascript" src="byob.js?version=2018-06-21"></script>
-		<script type="text/javascript" src="tables.js?version=2018-06-21"></script>
-		<script type="text/javascript" src="symbols.js?version=2018-06-21"></script>
-		<script type="text/javascript" src="sketch.js?version=2018-06-21"></script>
-		<script type="text/javascript" src="xml.js?version=2018-06-21"></script>
-		<script type="text/javascript" src="store.js?version=2018-10-02"></script>
-		<script type="text/javascript" src="locale.js?version=2018-07-09"></script>
-		<script type="text/javascript" src="cloud.js?version=2018-10-02"></script>
-		<script type="text/javascript" src="sha512.js?version=2018-06-21"></script>
-		<script type="text/javascript" src="FileSaver.min.js?version=2018-06-21"></script>
+		<script type="text/javascript" src="src/morphic.js?version=2018-10-02"></script>
+		<script type="text/javascript" src="src/widgets.js?version=2018-10-02"></script>
+		<script type="text/javascript" src="src/blocks.js?version=2018-10-02"></script>
+		<script type="text/javascript" src="src/threads.js?version=2018-10-02"></script>
+		<script type="text/javascript" src="src/objects.js?version=2018-10-02"></script>
+		<script type="text/javascript" src="src/gui.js?version=2018-10-02"></script>
+		<script type="text/javascript" src="src/paint.js?version=2018-10-02"></script>
+		<script type="text/javascript" src="src/lists.js?version=2018-10-02"></script>
+		<script type="text/javascript" src="src/byob.js?version=2018-10-02"></script>
+		<script type="text/javascript" src="src/tables.js?version=2018-10-02"></script>
+		<script type="text/javascript" src="src/symbols.js?version=2018-10-02"></script>
+		<script type="text/javascript" src="src/sketch.js?version=2018-10-02"></script>
+		<script type="text/javascript" src="src/xml.js?version=2018-10-02"></script>
+		<script type="text/javascript" src="src/store.js?version=2018-10-02"></script>
+		<script type="text/javascript" src="src/locale.js?version=2018-10-02"></script>
+		<script type="text/javascript" src="src/cloud.js?version=2018-10-02"></script>
+		<script type="text/javascript" src="src/sha512.js?version=2018-10-02"></script>
+		<script type="text/javascript" src="src/FileSaver.min.js?version=2018-10-02"></script>
 		<script type="text/javascript">
 			var world;
 			window.onload = function () {
diff --git a/FileSaver.min.js b/src/FileSaver.min.js
similarity index 100%
rename from FileSaver.min.js
rename to src/FileSaver.min.js
diff --git a/blocks.js b/src/blocks.js
similarity index 100%
rename from blocks.js
rename to src/blocks.js
diff --git a/byob.js b/src/byob.js
similarity index 100%
rename from byob.js
rename to src/byob.js
diff --git a/cloud.js b/src/cloud.js
similarity index 100%
rename from cloud.js
rename to src/cloud.js
diff --git a/gui.js b/src/gui.js
similarity index 99%
rename from gui.js
rename to src/gui.js
index 65a091ce..faceaee2 100644
--- a/gui.js
+++ b/src/gui.js
@@ -2002,7 +2002,7 @@ IDE_Morph.prototype.droppedBinary = function (anArrayBuffer, name) {
         ypr.id = 'ypr';
         ypr.onload = function () {loadYPR(anArrayBuffer, name); };
         document.head.appendChild(ypr);
-        ypr.src = 'ypr.js';
+        ypr.src = this.resourceURL('src', 'ypr.js');
     } else {
         loadYPR(anArrayBuffer, name);
     }
diff --git a/lists.js b/src/lists.js
similarity index 100%
rename from lists.js
rename to src/lists.js
diff --git a/locale.js b/src/locale.js
similarity index 100%
rename from locale.js
rename to src/locale.js
diff --git a/morphic.js b/src/morphic.js
similarity index 100%
rename from morphic.js
rename to src/morphic.js
diff --git a/morphic.txt b/src/morphic.txt
similarity index 100%
rename from morphic.txt
rename to src/morphic.txt
diff --git a/objects.js b/src/objects.js
similarity index 100%
rename from objects.js
rename to src/objects.js
diff --git a/paint.js b/src/paint.js
similarity index 100%
rename from paint.js
rename to src/paint.js
diff --git a/sha512.js b/src/sha512.js
similarity index 100%
rename from sha512.js
rename to src/sha512.js
diff --git a/sketch.js b/src/sketch.js
similarity index 100%
rename from sketch.js
rename to src/sketch.js
diff --git a/store.js b/src/store.js
similarity index 100%
rename from store.js
rename to src/store.js
diff --git a/symbols.js b/src/symbols.js
similarity index 100%
rename from symbols.js
rename to src/symbols.js
diff --git a/tables.js b/src/tables.js
similarity index 100%
rename from tables.js
rename to src/tables.js
diff --git a/threads.js b/src/threads.js
similarity index 100%
rename from threads.js
rename to src/threads.js
diff --git a/widgets.js b/src/widgets.js
similarity index 100%
rename from widgets.js
rename to src/widgets.js
diff --git a/xml.js b/src/xml.js
similarity index 100%
rename from xml.js
rename to src/xml.js
diff --git a/ypr.js b/src/ypr.js
similarity index 100%
rename from ypr.js
rename to src/ypr.js