diff --git a/CHANGELOG b/CHANGELOG
index f96d5905a..5e9683ce5 100644
--- a/CHANGELOG
+++ b/CHANGELOG
@@ -1,6 +1,7 @@
 CHANGELOG RoundCube Webmail
 ===========================
 
+- Fix text wrapping in HTML editor after switching from plain text to HTML (#1485521)
 - Fix auto-complete function hangs with plus sign (#1485815)
 - Fix AJAX requests errors handler (#1485000)
 - Speed up message list displaying on IE
diff --git a/program/js/app.js b/program/js/app.js
index 43e0aa984..65b7c835d 100644
--- a/program/js/app.js
+++ b/program/js/app.js
@@ -3789,6 +3789,13 @@ function rcube_webmail()
       });
     }
 
+  this.plain2html = function(plainText, id)
+    {
+    this.set_busy(true, 'converting');
+    $(document.getElementById(id)).val('<pre>'+plainText+'</pre>');
+    this.set_busy(false);
+    }
+
 
   /********************************************************/
   /*********        remote request methods        *********/
diff --git a/program/js/editor.js b/program/js/editor.js
index 7f937b2b8..6826af847 100644
--- a/program/js/editor.js
+++ b/program/js/editor.js
@@ -75,9 +75,8 @@ function rcmail_toggle_editor(ishtml, textAreaId, flagElement)
   if (ishtml)
     {
     rcmail.display_spellcheck_controls(false);
-    var htmlText = "<pre>" + composeElement.value + "</pre>";
 
-    composeElement.value = htmlText;
+    rcmail.plain2html(composeElement.value, textAreaId);
     tinyMCE.execCommand('mceAddControl', true, textAreaId);
     if (flagElement && (flag = rcube_find_object(flagElement)))
       flag.value = '1';
diff --git a/skins/default/editor_content.css b/skins/default/editor_content.css
index 31a0a592e..099b4248a 100644
--- a/skins/default/editor_content.css
+++ b/skins/default/editor_content.css
@@ -13,3 +13,13 @@ body {
 	margin-top: 2px;
 }
 
+pre
+{
+	margin: 0;
+	padding: 0;
+        white-space: -o-pre-wrap !important;
+	white-space: -moz-pre-wrap !important;
+	white-space: pre-wrap !important;
+	white-space: pre;
+	word-wrap: break-word; /* IE (and Safari) */
+}