Index: trunk/src/org/openstreetmap/josm/gui/dialogs/properties/TagEditHelper.java
===================================================================
--- trunk/src/org/openstreetmap/josm/gui/dialogs/properties/TagEditHelper.java	(revision 15565)
+++ trunk/src/org/openstreetmap/josm/gui/dialogs/properties/TagEditHelper.java	(revision 15567)
@@ -124,4 +124,8 @@
     public static final int MAX_LRU_TAGS_NUMBER = 30;
 
+    /** Autocomplete keys by default */
+    public static final BooleanProperty AUTOCOMPLETE_KEYS = new BooleanProperty("properties.autocomplete-keys", true);
+    /** Autocomplete values by default */
+    public static final BooleanProperty AUTOCOMPLETE_VALUES = new BooleanProperty("properties.autocomplete-values", true);
     /** Use English language for tag by default */
     public static final BooleanProperty PROPERTY_FIX_TAG_LOCALE = new BooleanProperty("properties.fix-tag-combobox-locale", false);
@@ -715,4 +719,6 @@
             keys = new AutoCompletingComboBox();
             values = new AutoCompletingComboBox();
+            keys.setAutocompleteEnabled(AUTOCOMPLETE_KEYS.get());
+            values.setAutocompleteEnabled(AUTOCOMPLETE_VALUES.get());
 
             mainPanel.add(new JLabel("<html>"+trn("This will change up to {0} object.",
Index: trunk/src/org/openstreetmap/josm/gui/tagging/ac/AutoCompletingComboBox.java
===================================================================
--- trunk/src/org/openstreetmap/josm/gui/tagging/ac/AutoCompletingComboBox.java	(revision 15565)
+++ trunk/src/org/openstreetmap/josm/gui/tagging/ac/AutoCompletingComboBox.java	(revision 15567)
@@ -344,5 +344,10 @@
     }
 
-    protected void setAutocompleteEnabled(boolean autocompleteEnabled) {
+    /**
+     * Sets whether the autocompletion is enabled
+     * @param autocompleteEnabled {@code true} to enable autocompletion
+     * @since 15567 (visibility)
+     */
+    public void setAutocompleteEnabled(boolean autocompleteEnabled) {
         this.autocompleteEnabled = autocompleteEnabled;
     }
