diff --git a/content/filtaquilla-util.js b/content/filtaquilla-util.js
index e5d13df..28ea610 100644
--- a/content/filtaquilla-util.js
+++ b/content/filtaquilla-util.js
@@ -331,7 +331,7 @@ FiltaQuilla.Util = {
   showAboutConfig: function(clickedElement, filter, readOnly) {
     const name = "Preferences:ConfigManager",
 		      util = FiltaQuilla.Util;
-    let uri = "chrome://global/content/config.xul";
+    let uri = "chrome://global/content/config.xhtml";
 		if (util.Application)
 			uri += "?debug";
 
diff --git a/content/filtaquilla.js b/content/filtaquilla.js
index 30c598c..066fbca 100644
--- a/content/filtaquilla.js
+++ b/content/filtaquilla.js
@@ -297,7 +297,7 @@
         apply: function(aMsgHdrs, aActionValue, aListener, aType, aMsgWindow) {
           _aListener = aListener;
           var srcFolder = aMsgHdrs.queryElementAt(0, Ci.nsIMsgDBHdr).folder;
-          _dstFolder = MailUtils.getFolderForURI(aActionValue, false);
+          _dstFolder = MailUtils.getExistingFolder(aActionValue, false);
           // store the messages Ids to use post-copy
           _messageIds = [];
           for (var i = 0; i < aMsgHdrs.length; i++)
@@ -312,7 +312,7 @@
         },
         isValidForType: function(type, scope) { return type == Ci.nsMsgFilterType.Manual && copyAsReadEnabled;},
         validateActionValue: function(aActionValue, aFilterFolder, type) {
-          var msgFolder = MailUtils.getFolderForURI(aActionValue, false);
+          var msgFolder = MailUtils.getExistingFolder(aActionValue, false);
           if (!msgFolder || !msgFolder.canFileMessages)
           {
             return self.strings.GetStringFromName("filtaquilla.mustSelectFolder");
@@ -535,7 +535,7 @@
             let uri = hdr.folder.generateMessageURI(hdr.messageKey);
             Services.console.logStringMessage("Queue filter request to print message: " + hdr.subject);
             let printDialog =
-              window.openDialog("chrome://messenger/content/msgPrintEngine.xul", "",
+              window.openDialog("chrome://messenger/content/msgPrintEngine.xhtml", "",
                                 "chrome,dialog=no,all,centerscreen",
                                 1, [uri], statusFeedback,
                                 false, Ci.nsIMsgPrintEngine.MNAB_PRINT_MSG, window);
@@ -831,11 +831,14 @@
       name: self.strings.GetStringFromName("filtaquilla.moveLater.name"),
       apply: function(aMsgHdrs, aActionValue, copyListener, filterType, msgWindow) {
         let srcFolder = aMsgHdrs.queryElementAt(0, Ci.nsIMsgDBHdr).folder;
-        let dstFolder = MailUtils.getFolderForURI(aActionValue, false);
+        let dstFolder = MailUtils.getExistingFolder(aActionValue, false);
         // store the messages uris to use later
         let timer = Cc["@mozilla.org/timer;1"].createInstance(Ci.nsITimer);
         let currentIndex = moveLaterIndex++;
         moveLaterTimers[currentIndex] = timer;
+        // the message headers array gets cleared by Thunderbird 78! we need to save it elswhere
+        
+        
         let callback = new MoveLaterNotify(aMsgHdrs, srcFolder, dstFolder, currentIndex);
         timer.initWithCallback(callback, MOVE_LATER_DELAY, Ci.nsITimer.TYPE_ONE_SHOT);
       },
@@ -1565,9 +1568,14 @@
   };
 
   // local private functions
-
+  // constructor for the MoveLaterNotify object
   function MoveLaterNotify(aMessages, aSource, aDestination, aTimerIndex)  {
-    this.messages = aMessages;
+    // thunderbird 78 tidies up the aMessages array during apply, so we need to make a copy:
+    this.messages = Cc["@mozilla.org/array;1"].createInstance(Ci.nsIMutableArray)
+    // clone the messages array
+    for (let i=0; i<aMessages.length; i++) {
+      this.messages.appendElement(aMessages.queryElementAt(i, Ci.nsIMsgDBHdr), false);
+    }
     this.source = aSource;
     this.destination = aDestination;
     this.timerIndex = aTimerIndex;
@@ -1578,6 +1586,7 @@
     // Check the moveLater values for the headers. If this is set by a routine
     //  with a reliable finish listener, then we will wait until that is done to
     //  move. For others, we move on the first callback after the delay.
+    const isMove = true, allowUndo = false;
     let moveLaterCount = -1;
     this.recallCount--;
     for (let i = 0; i < this.messages.length; i++) {
@@ -1588,14 +1597,18 @@
           moveLaterCount = localCount;
       } catch(e) {}
     }
-    //dl('moveLaterCount is ' + moveLaterCount + ' recallCount is ' + this.recallCount);
     if ( (moveLaterCount <= 0) || (this.recallCount <= 0)) { // execute move    
       const copyService = Cc["@mozilla.org/messenger/messagecopyservice;1"]
                             .getService(Ci.nsIMsgCopyService);
-      copyService.CopyMessages(this.source, this.messages,
-                               this.destination, true,
-                               null, null, false);
+      copyService.CopyMessages(this.source, 
+                               this.messages,
+                               this.destination, 
+                               isMove,
+                               null, 
+                               null, 
+                               allowUndo);
       moveLaterTimers[this.timerIndex] = null;
+      this.messages.clear(); // release all objects, just in case.
     }
     else // reschedule another check
       moveLaterTimers[this.timerIndex].initWithCallback(this, MOVE_LATER_DELAY, Ci.nsITimer.TYPE_ONE_SHOT);
diff --git a/content/fq_FilterEditor.js b/content/fq_FilterEditor.js
index 221780b..b3ac410 100644
--- a/content/fq_FilterEditor.js
+++ b/content/fq_FilterEditor.js
@@ -425,22 +425,7 @@
 
 // ***********  CONDITIONS  ***********
 
-  
-  // I think for search custom elements, we need to patch MozSearchAttribute?
-  function getAttributeChildNode(type) {
-    const elementMapping = {
-      // search values - custom  elements
-      "filtaquilla@mesquilla.com#subjectRegex" : "filtaquilla-search-value-textbox",
-      "filtaquilla@mesquilla.com#attachmentRegex" : "filtaquilla-search-value-textbox",
-      "filtaquilla@mesquilla.com#headerRegex" : "filtaquilla-search-value-textbox",
-      "filtaquilla@mesquilla.com#searchBcc" : "filtaquilla-search-value-textbox",
-      "filtaquilla@mesquilla.com#folderName" : "filtaquilla-search-value-textbox",
-      
-    };
-    const elementName = elementMapping[type];
-    return elementName ? document.createXULElement(elementName) : null;
-  }
-  
+    
   function patchFiltaQuillaJavaScriptCondition(es) {
     // bindings.xml#javascript: inject a JS editor. Script returns true or false
     // add a class fq-js to the container element!
diff --git a/manifest.json b/manifest.json
index e1fe202..5d0cab1 100644
--- a/manifest.json
+++ b/manifest.json
@@ -2,7 +2,7 @@
   "manifest_version" : 2,
   "name" : "FiltaQuilla",
   "description" : "Mail filter custom actions and searches",
-  "version" : "3.0pre40",
+  "version" : "3.0pre44",
   "default_locale": "en",
   "author" : "R Kent James,Axel Grude",
   "developer" : {
diff --git a/skin/filtaquilla.css b/skin/filtaquilla.css
index f601b21..2457ba2 100644
--- a/skin/filtaquilla.css
+++ b/skin/filtaquilla.css
@@ -62,8 +62,9 @@ menulist.flexinput {
 
 
 
-/* JavaScript editor */
+/* JavaScript editor
+  OBSOLETE!
 .search-value-custom[searchAttribute="filtaquilla@mesquilla.com#javascript"] {
   -moz-binding: url("chrome://filtaquilla/content/bindings.xml#javascript");
 }
-
+ */