--- a/netwerk/base/nsIBrowserSearchService.idl
+++ b/netwerk/base/nsIBrowserSearchService.idl
@@ -410,16 +410,26 @@ interface nsIBrowserSearchService : nsIS
    *
    * @returns an array of nsISearchEngine objects.
    */
   void getDefaultEngines(
             [optional] out unsigned long engineCount,
             [retval, array, size_is(engineCount)] out nsISearchEngine engines);
 
   /**
+   * Returns an array of search engines installed by a given extension.
+   *
+   * @returns an array of nsISearchEngine objects.
+   */
+  void getEnginesByExtensionID(in AString extensionID,
+            [optional] out unsigned long engineCount,
+            [retval, array, size_is(engineCount)] out nsISearchEngine engines);
+
+
+  /**
    * Moves a visible search engine.
    *
    * @param  engine
    *         The engine to move.
    * @param  newIndex
    *         The engine's new index in the set of visible engines.
    *
    * @throws NS_ERROR_FAILURE if newIndex is out of bounds, or if engine is

--- a/toolkit/components/search/nsSearchService.js
+++ b/toolkit/components/search/nsSearchService.js
@@ -3987,16 +3987,27 @@ SearchService.prototype = {
       return a.name.localeCompare(b.name);
     }
     engines.sort(compareEngines);
 
     aCount.value = engines.length;
     return engines;
   },
 
+  getEnginesByExtensionID: function SRCH_SVC_getEngines(aExtensionID, aCount) {
+    this._ensureInitialized();
+    LOG("getEngines: getting all engines for " + aExtensionID);
+    var engines = this._getSortedEngines(true).filter(function(engine) {
+      return engine._extensionID == aExtensionID;
+    });
+    aCount.value = engines.length;
+    return engines;
+  },
+
+
   getEngineByName: function SRCH_SVC_getEngineByName(aEngineName) {
     this._ensureInitialized();
     return this._engines[aEngineName] || null;
   },
 
   getEngineByAlias: function SRCH_SVC_getEngineByAlias(aAlias) {
     this._ensureInitialized();
     for (var engineName in this._engines) {

new file mode 100644
--- /dev/null
+++ b/toolkit/components/search/tests/xpcshell/test_addEngineWithExtensionID.js
@@ -0,0 +1,25 @@
+/* Any copyright is dedicated to the Public Domain.
+   http://creativecommons.org/publicdomain/zero/1.0/ */
+
+"use strict";
+
+const kSearchEngineID = "addEngineWithDetails_test_engine";
+const kSearchEngineURL = "http://example.com/?search={searchTerms}";
+const kSearchTerm = "foo";
+const kExtensionID = "extension@mozilla.com";
+
+add_task(async function test_addEngineWithExtensionID() {
+  do_check_false(Services.search.isInitialized);
+
+  await asyncInit();
+
+  Services.search.addEngineWithDetails(kSearchEngineID, "", "", "", "get",
+                                       kSearchEngineURL, kExtensionID);
+
+  let engine = Services.search.getEngineByName(kSearchEngineID);
+  do_check_neq(engine, null);
+
+  let engines = Services.search.getEnginesByExtensionID(kExtensionID);
+  do_check_eq(engines.length, 1);
+  do_check_eq(engines[0], engine);
+});

--- a/toolkit/components/search/tests/xpcshell/xpcshell.ini
+++ b/toolkit/components/search/tests/xpcshell/xpcshell.ini
@@ -91,12 +91,13 @@ tags = addons
 [test_selectedEngine.js]
 [test_geodefaults.js]
 [test_hidden.js]
 [test_currentEngine_fallback.js]
 [test_require_engines_in_cache.js]
 [test_svg_icon.js]
 [test_searchReset.js]
 [test_addEngineWithDetails.js]
+[test_addEngineWithExtensionID.js]
 [test_chromeresource_icon1.js]
 [test_chromeresource_icon2.js]
 [test_engineUpdate.js]
 [test_paramSubstitution.js]