--- a/toolkit/components/places/PlacesSearchAutocompleteProvider.jsm
+++ b/toolkit/components/places/PlacesSearchAutocompleteProvider.jsm
@@ -59,16 +59,17 @@ const SearchAutocompleteProviderInternal
 
   initialized: false,
 
   observe: function (subject, topic, data) {
     switch (data) {
       case "engine-added":
       case "engine-changed":
       case "engine-removed":
+      case "engine-current":
         this._refresh();
     }
   },
 
   _refresh: function () {
     this.priorityMatches = [];
     this.aliasMatches = [];
     this.defaultMatch = null;

--- a/toolkit/components/places/tests/unifiedcomplete/test_searchEngine_current.js
+++ b/toolkit/components/places/tests/unifiedcomplete/test_searchEngine_current.js
@@ -26,10 +26,22 @@ add_task(function*() {
 
   do_log_info("search engine, multiple words");
   yield check_autocomplete({
     search: "mozzarella cheese",
     searchParam: "enable-actions",
     matches: [ { uri: makeActionURI("searchengine", {engineName: "MozSearch", input: "mozzarella cheese", searchQuery: "mozzarella cheese"}), title: "MozSearch" }, ]
   });
 
+  do_log_info("search engine, after current engine has changed");
+  Services.search.addEngineWithDetails("MozSearch2", "", "", "", "GET",
+                                       "http://s.example.com/search2");
+  engine = Services.search.getEngineByName("MozSearch2");
+  notEqual(Services.search.currentEngine, engine, "New engine shouldn't be the current engine yet");
+  Services.search.currentEngine = engine;
+  yield check_autocomplete({
+    search: "mozilla",
+    searchParam: "enable-actions",
+    matches: [ { uri: makeActionURI("searchengine", {engineName: "MozSearch2", input: "mozilla", searchQuery: "mozilla"}), title: "MozSearch2" }, ]
+  });
+
   yield cleanup();
 });
\ No newline at end of file