diff --git a/src/calibre/ebooks/htmlz/output.py b/src/calibre/ebooks/htmlz/output.py
index 1140428f21..7cdf04bcdb 100644
--- a/src/calibre/ebooks/htmlz/output.py
+++ b/src/calibre/ebooks/htmlz/output.py
@@ -52,8 +52,7 @@ class HTMLZOutput(OutputFormatPlugin):
         else:
             from calibre.ebooks.htmlz.oeb2html import OEB2HTMLClassCSSizer as OEB2HTMLizer
 
-
-        with TemporaryDirectory('_txtz_output') as tdir:
+        with TemporaryDirectory('_htmlz_output') as tdir:
             htmlizer = OEB2HTMLizer(log)
             html = htmlizer.oeb2html(oeb_book, opts)
 
diff --git a/src/calibre/gui2/convert/htmlz_output.py b/src/calibre/gui2/convert/htmlz_output.py
index f1197175f9..6e9f5bd68c 100644
--- a/src/calibre/gui2/convert/htmlz_output.py
+++ b/src/calibre/gui2/convert/htmlz_output.py
@@ -17,10 +17,10 @@ class PluginWidget(Widget, Ui_Form):
     ICON = I('mimetypes/html.png')
 
     def __init__(self, parent, get_option, get_help, db=None, book_id=None):
-        Widget.__init__(self, parent, ['css_type', 'class_style'])
+        Widget.__init__(self, parent, ['htmlz_css_type', 'htmlz_class_style'])
         self.db, self.book_id = db, book_id
-        for x in get_option('css_type').option.choices:
-            self.opt_css_type.addItem(x)
-        for x in get_option('class_style').option.choices:
-            self.opt_class_style.addItem(x)
+        for x in get_option('htmlz_css_type').option.choices:
+            self.opt_htmlz_css_type.addItem(x)
+        for x in get_option('htmlz_class_style').option.choices:
+            self.opt_htmlz_class_style.addItem(x)
         self.initialize_options(get_option, get_help, db, book_id)
diff --git a/src/calibre/gui2/convert/htmlz_output.ui b/src/calibre/gui2/convert/htmlz_output.ui
index 2cdd7594ab..7593300653 100644
--- a/src/calibre/gui2/convert/htmlz_output.ui
+++ b/src/calibre/gui2/convert/htmlz_output.ui
@@ -33,12 +33,12 @@
       <string>How to handle CSS</string>
      </property>
      <property name="buddy">
-      <cstring>opt_css_type</cstring>
+      <cstring>opt_htmlz_css_type</cstring>
      </property>
     </widget>
    </item>
    <item row="0" column="1">
-    <widget class="QComboBox" name="opt_css_type">
+    <widget class="QComboBox" name="opt_htmlz_css_type">
      <property name="minimumContentsLength">
       <number>20</number>
      </property>
@@ -52,7 +52,7 @@
     </widget>
    </item>
    <item row="1" column="1">
-    <widget class="QComboBox" name="opt_class_style"/>
+    <widget class="QComboBox" name="opt_htmlz_class_style"/>
    </item>
   </layout>
  </widget>