diff --git a/toolkit/content/widgets/findbar.xml b/toolkit/content/widgets/findbar.xml
index 1812a507f84c..72e54e18d0dd 100644
--- a/toolkit/content/widgets/findbar.xml
+++ b/toolkit/content/widgets/findbar.xml
@@ -110,6 +110,13 @@
         findbar.browser.finder.enableSelection();
       ]]></handler>
 
+#ifdef XP_MACOSX
+      <handler event="focus"><![CDATA[
+        let findbar = this.findbar;
+        findbar._onFindFieldFocus();
+      ]]></handler>
+#endif
+
       <handler event="compositionstart"><![CDATA[
         // Don't close the find toolbar while IME is composing.
         let findbar = this.findbar;
@@ -1045,8 +1052,17 @@
             userWantsPrefill =
               prefsvc.getBoolPref("accessibility.typeaheadfind.prefillwithselection");
 
-          let initialString = (this.prefillWithSelection && userWantsPrefill) ?
-                              this._getInitialSelection() : null;
+          let initialString = null;
+          if (this.prefillWithSelection && userWantsPrefill)
+            initialString = this._getInitialSelection();
+#ifdef XP_MACOSX
+          if (!initialString) {
+            let clipboardSearchString = this.browser.finder.clipboardSearchString;
+            if (clipboardSearchString)
+              initialString = clipboardSearchString;
+          }
+#endif
+
           if (initialString)
             this._findField.value = initialString;
 
@@ -1102,6 +1118,32 @@
         ]]></body>
       </method>
 
+#ifdef XP_MACOSX
+      <!--
+        - Fetches the currently selected text and sets that as the text to search
+        - next. This is a MacOS specific feature.
+      -->
+      <method name="onFindSelectionCommand">
+        <body><![CDATA[
+          let searchString = this.browser.finder.setSearchStringToSelection();
+          if (searchString)
+            this._findField.value = searchString;
+        ]]></body>
+      </method>
+
+      <method name="_onFindFieldFocus">
+        <body><![CDATA[
+          let clipboardSearchString = this._browser.finder.clipboardSearchString;
+          if (clipboardSearchString && this._findField.value != clipboardSearchString) {
+            this._findField.value = clipboardSearchString;
+            // Changing the search string makes the previous status invalid, so
+            // we better clear it here.
+            this._updateStatusUI();
+          }
+        ]]></body>
+      </method>
+#endif
+
       <!--
         - This handles all the result changes for both
         - type-ahead-find and highlighting.
@@ -1119,6 +1161,8 @@
       <method name="onFindResult">
         <parameter name="aData"/>
         <body><![CDATA[
+          if (this._findField.value != this.browser.finder.searchString)
+            this._findField.value = this.browser.finder.searchString;
           this._updateStatusUI(aData.result, aData.findBackwards);
           this._updateStatusUIBar(aData.linkURL);
 
diff --git a/toolkit/modules/Finder.jsm b/toolkit/modules/Finder.jsm
index 7de2e424389c..5bf4c5b91711 100644
--- a/toolkit/modules/Finder.jsm
+++ b/toolkit/modules/Finder.jsm
@@ -12,6 +12,16 @@ Cu.import("resource://gre/modules/XPCOMUtils.jsm");
 Cu.import("resource://gre/modules/Geometry.jsm");
 Cu.import("resource://gre/modules/Services.jsm");
 
+XPCOMUtils.defineLazyServiceGetter(this, "TextToSubURIService",
+                                         "@mozilla.org/intl/texttosuburi;1",
+                                         "nsITextToSubURI");
+XPCOMUtils.defineLazyServiceGetter(this, "Clipboard",
+                                         "@mozilla.org/widget/clipboard;1",
+                                         "nsIClipboard");
+XPCOMUtils.defineLazyServiceGetter(this, "ClipboardHelper",
+                                         "@mozilla.org/widget/clipboardhelper;1",
+                                         "nsIClipboardHelper");
+
 function Finder(docShell) {
   this._fastFind = Cc["@mozilla.org/typeaheadfind;1"].createInstance(Ci.nsITypeAheadFind);
   this._fastFind.init(docShell);
@@ -38,6 +48,7 @@ Finder.prototype = {
 
   _notify: function (aSearchString, aResult, aFindBackwards, aDrawOutline) {
     this._searchString = aSearchString;
+    this.clipboardSearchString = aSearchString
     this._outlineLink(aDrawOutline);
 
     let foundLink = this._fastFind.foundLink;
@@ -48,12 +59,7 @@ Finder.prototype = {
       if (ownerDoc)
         docCharset = ownerDoc.characterSet;
 
-      if (!this._textToSubURIService) {
-        this._textToSubURIService = Cc["@mozilla.org/intl/texttosuburi;1"]
-                                      .getService(Ci.nsITextToSubURI);
-      }
-
-      linkURL = this._textToSubURIService.unEscapeURIForUI(docCharset, foundLink.href);
+      linkURL = TextToSubURIService.unEscapeURIForUI(docCharset, foundLink.href);
     }
 
     let data = {
@@ -70,9 +76,48 @@ Finder.prototype = {
   },
 
   get searchString() {
+    if (!this._searchString && this._fastFind.searchString)
+      this._searchString = this._fastFind.searchString;
     return this._searchString;
   },
 
+  get clipboardSearchString() {
+    let searchString = "";
+    if (!Clipboard.supportsFindClipboard())
+      return searchString;
+
+    try {
+      let trans = Cc["@mozilla.org/widget/transferable;1"]
+                    .createInstance(Ci.nsITransferable);
+      trans.init(this._getWindow()
+                     .QueryInterface(Ci.nsIInterfaceRequestor)
+                     .getInterface(Ci.nsIWebNavigation)
+                     .QueryInterface(Ci.nsILoadContext));
+      trans.addDataFlavor("text/unicode");
+
+      Clipboard.getData(trans, Ci.nsIClipboard.kFindClipboard);
+
+      let data = {};
+      let dataLen = {};
+      trans.getTransferData("text/unicode", data, dataLen);
+      if (data.value) {
+        data = data.value.QueryInterface(Ci.nsISupportsString);
+        searchString = data.toString();
+      }
+    } catch (ex) {}
+
+    return searchString;
+  },
+
+  set clipboardSearchString(aSearchString) {
+    if (!aSearchString || !Clipboard.supportsFindClipboard())
+      return;
+
+    ClipboardHelper.copyStringToClipboard(aSearchString,
+                                          Ci.nsIClipboard.kFindClipboard,
+                                          this._getWindow().document);
+  },
+
   set caseSensitive(aSensitive) {
     this._fastFind.caseSensitive = aSensitive;
   },
@@ -105,6 +150,25 @@ Finder.prototype = {
     this._notify(searchString, result, aFindBackwards, aDrawOutline);
   },
 
+  /**
+   * Forcibly set the search string of the find clipboard to the currently
+   * selected text in the window, on supported platforms (i.e. OSX).
+   */
+  setSearchStringToSelection: function() {
+    // Find the selected text.
+    let selection = this._getWindow().getSelection();
+    // Don't go for empty selections.
+    if (!selection.rangeCount)
+      return null;
+    let searchString = (selection.toString() || "").trim();
+    // Empty strings are rather useless to search for.
+    if (!searchString.length)
+      return null;
+
+    this.clipboardSearchString = searchString;
+    return searchString;
+  },
+
   highlight: function (aHighlight, aWord) {
     let found = this._highlight(aHighlight, aWord, null);
     if (aHighlight) {
