--- a/browser/components/preferences/sanitize.xul
+++ b/browser/components/preferences/sanitize.xul
@@ -47,16 +47,17 @@
   %brandDTD;
   %sanitizeDTD;
 ]>
 
 <prefwindow id="SanitizeDialog" type="child"
             xmlns="http://www.mozilla.org/keymaster/gatekeeper/there.is.only.xul"
             dlgbuttons="accept,cancel,help"
             ondialoghelp="openPrefsHelp()"
+            style="width: &dialog.width;;"
             title="&sanitizePrefs2.title;">
 
   <script type="application/javascript" src="chrome://browser/content/utilityOverlay.js"/>
 
   <prefpane id="SanitizeDialogPane"
             helpTopic="prefs-clear-private-data">
 
     <preferences>
@@ -70,49 +71,67 @@
       <preference id="privacy.item.sessions"              name="privacy.item.sessions"              type="bool"/>
       <preference id="privacy.item.siteSettings"          name="privacy.item.siteSettings"          type="bool"/>
     </preferences>
 
     <description>&clearDataSettings2.label;</description>
 
     <groupbox orient="horizontal">
       <caption label="&historySection.label;"/>
-      <vbox style="width: &column.width;">
-        <checkbox label="&itemBrowsingHistory.label;"
-                  accesskey="&itemBrowsingHistory.accesskey;"
-                  preference="privacy.item.history"/>
-        <checkbox label="&itemDownloadHistory.label;"
-                  accesskey="&itemDownloadHistory.accesskey;"
-                  preference="privacy.item.downloads"/>
-        <checkbox label="&itemFormSearchHistory.label;"
-                  accesskey="&itemFormSearchHistory.accesskey;"
-                  preference="privacy.item.formdata"/>
-      </vbox>
-      <vbox style="width: &column.width;">
-        <checkbox label="&itemCookies.label;"
-                  accesskey="&itemCookies.accesskey;"
-                  preference="privacy.item.cookies"/>
-        <checkbox label="&itemActiveLogins.label;"
-                  accesskey="&itemActiveLogins.accesskey;"
-                  preference="privacy.item.sessions"/>
-        <checkbox label="&itemCache.label;"
-                  accesskey="&itemCache.accesskey;"
-                  preference="privacy.item.cache"/>
-      </vbox>
+      <grid flex="1">
+        <columns>
+          <column style="width: &column.width;"/>
+          <column flex="1"/>
+        </columns>
+        <rows>
+          <row>
+            <checkbox label="&itemBrowsingHistory.label;"
+                      accesskey="&itemBrowsingHistory.accesskey;"
+                      preference="privacy.item.history"/>
+            <checkbox label="&itemCookies.label;"
+                      accesskey="&itemCookies.accesskey;"
+                      preference="privacy.item.cookies"/>
+          </row>
+          <row>
+            <checkbox label="&itemDownloadHistory.label;"
+                      accesskey="&itemDownloadHistory.accesskey;"
+                      preference="privacy.item.downloads"/>
+            <checkbox label="&itemActiveLogins.label;"
+                      accesskey="&itemActiveLogins.accesskey;"
+                      preference="privacy.item.sessions"/>
+          </row>
+          <row>
+            <checkbox label="&itemFormSearchHistory.label;"
+                      accesskey="&itemFormSearchHistory.accesskey;"
+                      preference="privacy.item.formdata"/>
+            <checkbox label="&itemCache.label;"
+                      accesskey="&itemCache.accesskey;"
+                      preference="privacy.item.cache"/>
+          </row>
+        </rows>
+      </grid>
     </groupbox>
     <groupbox orient="horizontal">
       <caption label="&dataSection.label;"/>
-      <vbox style="width: &column.width;">
-        <checkbox label="&itemPasswords.label;"
-                  accesskey="&itemPasswords.accesskey;"
-                  preference="privacy.item.passwords"/>
-        <checkbox label="&itemSitePreferences.label;"
-                  accesskey="&itemSitePreferences.accesskey;"
-                  preference="privacy.item.siteSettings"/>
-      </vbox>
-      <vbox style="width: &column.width;">
-        <checkbox label="&itemOfflineApps.label;"
-                  accesskey="&itemOfflineApps.accesskey;"
-                  preference="privacy.item.offlineApps"/>
-      </vbox>
+      <grid flex="1">
+        <columns>
+          <column style="width: &column.width;"/>
+          <column flex="1"/>
+        </columns>
+        <rows>
+          <row>
+            <checkbox label="&itemPasswords.label;"
+                      accesskey="&itemPasswords.accesskey;"
+                      preference="privacy.item.passwords"/>
+            <checkbox label="&itemOfflineApps.label;"
+                      accesskey="&itemOfflineApps.accesskey;"
+                      preference="privacy.item.offlineApps"/>
+          </row>
+          <row>
+            <checkbox label="&itemSitePreferences.label;"
+                      accesskey="&itemSitePreferences.accesskey;"
+                      preference="privacy.item.siteSettings"/>
+          </row>
+        </rows>
+      </grid>
     </groupbox>
   </prefpane>
 </prefwindow>

--- a/browser/themes/winstripe/browser/preferences/preferences.css
+++ b/browser/themes/winstripe/browser/preferences/preferences.css
@@ -168,15 +168,8 @@ radio[pane=paneAdvanced][selected="true"
   padding-bottom: 8px;
 }
 
 /* bottom-most box containing a groupbox in a prefpane. Prevents the bottom
    of the groupbox from being cutoff */
 .bottomBox {
   padding-bottom: 4px;
 }
-
-/**
- * Clear Private Data
- */
-#SanitizeDialogPane > groupbox {
-  margin-top: 0;
-}