diff --git a/devtools/client/aboutdebugging/test/addons/test-devtools-webextension-nobg/manifest.json b/devtools/client/aboutdebugging/test/addons/test-devtools-webextension-nobg/manifest.json
index fdac2e227..289d8b918 100644
--- a/devtools/client/aboutdebugging/test/addons/test-devtools-webextension-nobg/manifest.json
+++ b/devtools/client/aboutdebugging/test/addons/test-devtools-webextension-nobg/manifest.json
@@ -3,7 +3,7 @@
   "name": "test-devtools-webextension-nobg",
   "version": "1.0",
   "applications": {
-    "goanna": {
+    "gecko": {
       "id": "test-devtools-webextension-nobg@mozilla.org"
     }
   }
diff --git a/devtools/client/aboutdebugging/test/addons/test-devtools-webextension/manifest.json b/devtools/client/aboutdebugging/test/addons/test-devtools-webextension/manifest.json
index fd4e57e81..f224e5dcf 100644
--- a/devtools/client/aboutdebugging/test/addons/test-devtools-webextension/manifest.json
+++ b/devtools/client/aboutdebugging/test/addons/test-devtools-webextension/manifest.json
@@ -3,7 +3,7 @@
   "name": "test-devtools-webextension",
   "version": "1.0",
   "applications": {
-    "goanna": {
+    "gecko": {
       "id": "test-devtools-webextension@mozilla.org"
     }
   },
diff --git a/devtools/client/aboutdebugging/test/browser_addons_reload.js b/devtools/client/aboutdebugging/test/browser_addons_reload.js
index 87a51fe41..f2ffb8cdf 100644
--- a/devtools/client/aboutdebugging/test/browser_addons_reload.js
+++ b/devtools/client/aboutdebugging/test/browser_addons_reload.js
@@ -148,7 +148,7 @@ add_task(function* reloadButtonRefreshesMetadata() {
     "name": "Temporary web extension",
     "version": "1.0",
     "applications": {
-      "goanna": {
+      "gecko": {
         "id": ADDON_ID
       }
     }
diff --git a/devtools/client/debugger/test/mochitest/addon-source/browser_dbg_addon_webext_contentscript/manifest.json b/devtools/client/debugger/test/mochitest/addon-source/browser_dbg_addon_webext_contentscript/manifest.json
index b3e1b610c..ebc834bf7 100644
--- a/devtools/client/debugger/test/mochitest/addon-source/browser_dbg_addon_webext_contentscript/manifest.json
+++ b/devtools/client/debugger/test/mochitest/addon-source/browser_dbg_addon_webext_contentscript/manifest.json
@@ -4,7 +4,7 @@
   "description": "test content script sources",
   "version": "0.1.0",
   "applications": {
-    "goanna": {
+    "gecko": {
       "id": "test-contentscript-sources@mozilla.com"
     }
   },
diff --git a/devtools/server/tests/unit/addons/web-extension-upgrade/manifest.json b/devtools/server/tests/unit/addons/web-extension-upgrade/manifest.json
index 49ac33831..f70b11efd 100644
--- a/devtools/server/tests/unit/addons/web-extension-upgrade/manifest.json
+++ b/devtools/server/tests/unit/addons/web-extension-upgrade/manifest.json
@@ -3,7 +3,7 @@
   "name": "Test Addons Actor Upgrade",
   "version": "1.0",
   "applications": {
-    "goanna": {
+    "gecko": {
       "id": "test-addons-actor@mozilla.org"
     }
   }
diff --git a/devtools/server/tests/unit/addons/web-extension/manifest.json b/devtools/server/tests/unit/addons/web-extension/manifest.json
index e49781b9d..d120cf3da 100644
--- a/devtools/server/tests/unit/addons/web-extension/manifest.json
+++ b/devtools/server/tests/unit/addons/web-extension/manifest.json
@@ -3,7 +3,7 @@
   "name": "Test Addons Actor",
   "version": "1.0",
   "applications": {
-    "goanna": {
+    "gecko": {
       "id": "test-addons-actor@mozilla.org"
     }
   }
diff --git a/devtools/server/tests/unit/addons/web-extension2/manifest.json b/devtools/server/tests/unit/addons/web-extension2/manifest.json
index 070a4dea6..57daae29d 100644
--- a/devtools/server/tests/unit/addons/web-extension2/manifest.json
+++ b/devtools/server/tests/unit/addons/web-extension2/manifest.json
@@ -3,7 +3,7 @@
   "name": "Test Addons Actor 2",
   "version": "1.0",
   "applications": {
-    "goanna": {
+    "gecko": {
       "id": "test-addons-actor2@mozilla.org"
     }
   }
diff --git a/jetpack/source/test/addons/embedded-webextension/webextension/manifest.json b/jetpack/source/test/addons/embedded-webextension/webextension/manifest.json
index aceaa2709..d2188e7ba 100644
--- a/jetpack/source/test/addons/embedded-webextension/webextension/manifest.json
+++ b/jetpack/source/test/addons/embedded-webextension/webextension/manifest.json
@@ -3,7 +3,7 @@
   "description": "",
   "version": "0.1.0",
   "applications": {
-    "goanna": {
+    "gecko": {
       "id": "embedded-webextension@jetpack"
     }
   },
diff --git a/mobile/android/components/extensions/test/mochitest/test_ext_pageAction.html b/mobile/android/components/extensions/test/mochitest/test_ext_pageAction.html
index aa02feb23..b13c551bd 100644
--- a/mobile/android/components/extensions/test/mochitest/test_ext_pageAction.html
+++ b/mobile/android/components/extensions/test/mochitest/test_ext_pageAction.html
@@ -61,7 +61,7 @@ add_task(function* test_pageAction() {
         },
       },
       "applications": {
-        "goanna": {
+        "gecko": {
           "id": "foo@bar.com",
         },
       },
diff --git a/toolkit/components/extensions/ExtensionTestCommon.jsm b/toolkit/components/extensions/ExtensionTestCommon.jsm
index 83535e6b0..0e72393e0 100644
--- a/toolkit/components/extensions/ExtensionTestCommon.jsm
+++ b/toolkit/components/extensions/ExtensionTestCommon.jsm
@@ -215,7 +215,7 @@ class ExtensionTestCommon {
           <RDF xmlns="http://www.w3.org/1999/02/22-rdf-syntax-ns#"
                xmlns:em="http://www.mozilla.org/2004/em-rdf#">
               <Description about="urn:mozilla:install-manifest"
-                  em:id="${manifest.applications.goanna.id}"
+                  em:id="${manifest.applications.gecko.id}"
                   em:name="${manifest.name}"
                   em:type="2"
                   em:version="${manifest.version}"
@@ -327,10 +327,10 @@ class ExtensionTestCommon {
 
     let id;
     if (data.manifest) {
-      if (data.manifest.applications && data.manifest.applications.goanna) {
-        id = data.manifest.applications.goanna.id;
-      } else if (data.manifest.browser_specific_settings && data.manifest.browser_specific_settings.goanna) {
-        id = data.manifest.browser_specific_settings.goanna.id;
+      if (data.manifest.applications && data.manifest.applications.gecko) {
+        id = data.manifest.applications.gecko.id;
+      } else if (data.manifest.browser_specific_settings && data.manifest.browser_specific_settings.gecko) {
+        id = data.manifest.browser_specific_settings.gecko.id;
       }
     }
     if (!id) {
diff --git a/toolkit/components/extensions/ExtensionXPCShellUtils.jsm b/toolkit/components/extensions/ExtensionXPCShellUtils.jsm
index ac0d1bffe..339709a19 100644
--- a/toolkit/components/extensions/ExtensionXPCShellUtils.jsm
+++ b/toolkit/components/extensions/ExtensionXPCShellUtils.jsm
@@ -29,7 +29,7 @@ XPCOMUtils.defineLazyGetter(this, "Management", () => {
 
 let BASE_MANIFEST = Object.freeze({
   "applications": Object.freeze({
-    "goanna": Object.freeze({
+    "gecko": Object.freeze({
       "id": "test@web.ext",
     }),
   }),
diff --git a/toolkit/components/extensions/schemas/manifest.json b/toolkit/components/extensions/schemas/manifest.json
index a7f3a4fce..09e6b56fb 100644
--- a/toolkit/components/extensions/schemas/manifest.json
+++ b/toolkit/components/extensions/schemas/manifest.json
@@ -22,7 +22,7 @@
             "type": "object",
             "optional": true,
             "properties": {
-              "goanna": {
+              "gecko": {
                 "$ref": "FirefoxSpecificProperties",
                 "optional": true
               }
@@ -33,7 +33,7 @@
             "type": "object",
             "optional": true,
             "properties": {
-              "goanna": {
+              "gecko": {
                 "$ref": "FirefoxSpecificProperties",
                 "optional": true
               }
diff --git a/toolkit/components/extensions/test/mochitest/test_chrome_ext_background_debug_global.html b/toolkit/components/extensions/test/mochitest/test_chrome_ext_background_debug_global.html
index f298926c2..d348cf21e 100644
--- a/toolkit/components/extensions/test/mochitest/test_chrome_ext_background_debug_global.html
+++ b/toolkit/components/extensions/test/mochitest/test_chrome_ext_background_debug_global.html
@@ -39,7 +39,7 @@ let extensionData = {
   useAddonManager: "temporary",
   background,
   manifest: {
-    applications: {goanna: {id: ID}},
+    applications: {gecko: {id: ID}},
   },
 };
 
diff --git a/toolkit/components/extensions/test/mochitest/test_chrome_ext_identity.html b/toolkit/components/extensions/test/mochitest/test_chrome_ext_identity.html
index d8611a871..c60807cb5 100644
--- a/toolkit/components/extensions/test/mochitest/test_chrome_ext_identity.html
+++ b/toolkit/components/extensions/test/mochitest/test_chrome_ext_identity.html
@@ -37,7 +37,7 @@ add_task(function* test_badAuthURI() {
   let extension = ExtensionTestUtils.loadExtension({
     manifest: {
       "applications": {
-        "goanna": {
+        "gecko": {
           "id": "identity@mozilla.org",
         },
       },
@@ -167,7 +167,7 @@ add_task(function* test_autoRedirect() {
   let extension = ExtensionTestUtils.loadExtension({
     manifest: {
       "applications": {
-        "goanna": {
+        "gecko": {
           "id": "identity@mozilla.org",
         },
       },
@@ -189,7 +189,7 @@ add_task(function* test_noRedirect() {
   let extension = ExtensionTestUtils.loadExtension({
     manifest: {
       "applications": {
-        "goanna": {
+        "gecko": {
           "id": "identity@mozilla.org",
         },
       },
@@ -214,7 +214,7 @@ add_task(function* test_interaction() {
   let extension = ExtensionTestUtils.loadExtension({
     manifest: {
       "applications": {
-        "goanna": {
+        "gecko": {
           "id": "identity@mozilla.org",
         },
       },
diff --git a/toolkit/components/extensions/test/mochitest/test_chrome_ext_storage_cleanup.html b/toolkit/components/extensions/test/mochitest/test_chrome_ext_storage_cleanup.html
index 10310f166..010769500 100644
--- a/toolkit/components/extensions/test/mochitest/test_chrome_ext_storage_cleanup.html
+++ b/toolkit/components/extensions/test/mochitest/test_chrome_ext_storage_cleanup.html
@@ -108,7 +108,7 @@ add_task(function* test_uninstall() {
   let extension = ExtensionTestUtils.loadExtension({
     background: writeData,
     manifest: {
-      applications: {goanna: {id: ID}},
+      applications: {gecko: {id: ID}},
       permissions: ["storage"],
     },
     useAddonManager: "temporary",
@@ -127,7 +127,7 @@ add_task(function* test_uninstall() {
   extension = ExtensionTestUtils.loadExtension({
     background: readData,
     manifest: {
-      applications: {goanna: {id: ID}},
+      applications: {gecko: {id: ID}},
       permissions: ["storage"],
     },
     useAddonManager: "temporary",
@@ -145,7 +145,7 @@ add_task(function* test_uninstall() {
   extension = ExtensionTestUtils.loadExtension({
     background: readData,
     manifest: {
-      applications: {goanna: {id: ID}},
+      applications: {gecko: {id: ID}},
       permissions: ["storage"],
     },
     useAddonManager: "temporary",
diff --git a/toolkit/components/extensions/test/mochitest/test_ext_contentscript.html b/toolkit/components/extensions/test/mochitest/test_ext_contentscript.html
index ba03e7b1c..39f1bfabd 100644
--- a/toolkit/components/extensions/test/mochitest/test_ext_contentscript.html
+++ b/toolkit/components/extensions/test/mochitest/test_ext_contentscript.html
@@ -40,13 +40,13 @@ add_task(function* test_contentscript() {
 
   function contentScript() {
     let manifest = browser.runtime.getManifest();
-    void manifest.applications.goanna.id;
+    void manifest.applications.gecko.id;
     chrome.runtime.sendMessage(["chrome-namespace-ok"]);
   }
 
   let extensionData = {
     manifest: {
-      applications: {goanna: {id: "contentscript@tests.mozilla.org"}},
+      applications: {gecko: {id: "contentscript@tests.mozilla.org"}},
       content_scripts: [
         {
           "matches": ["http://mochi.test/*/file_sample.html"],
diff --git a/toolkit/components/extensions/test/mochitest/test_ext_contentscript_create_iframe.html b/toolkit/components/extensions/test/mochitest/test_ext_contentscript_create_iframe.html
index 65a0f789a..667c1a6d8 100644
--- a/toolkit/components/extensions/test/mochitest/test_ext_contentscript_create_iframe.html
+++ b/toolkit/components/extensions/test/mochitest/test_ext_contentscript_create_iframe.html
@@ -34,14 +34,14 @@ add_task(function* test_contentscript_create_iframe() {
       browser.test.assertFalse(hasExtTabsAPI, "the created iframe should not be able to use privileged APIs (tabs)");
       browser.test.assertFalse(hasExtWindowsAPI, "the created iframe should not be able to use privileged APIs (windows)");
 
-      let {applications: {goanna: {id: expectedManifestGoannaId}}} = chrome.runtime.getManifest();
-      let {applications: {goanna: {id: actualManifestGoannaId}}} = manifest;
+      let {applications: {gecko: {id: expectedManifestGoannaId}}} = chrome.runtime.getManifest();
+      let {applications: {gecko: {id: actualManifestGoannaId}}} = manifest;
 
       browser.test.assertEq(actualManifestGoannaId, expectedManifestGoannaId,
                             "the add-on manifest should be accessible from the created iframe"
       );
 
-      let {applications: {goanna: {id: testGetManifestGoannaId}}} = testGetManifest;
+      let {applications: {gecko: {id: testGetManifestGoannaId}}} = testGetManifest;
 
       browser.test.assertEq(testGetManifestGoannaId, expectedManifestGoannaId,
                               "GET_MANIFEST() returns manifest data before extension unload"
@@ -84,7 +84,7 @@ add_task(function* test_contentscript_create_iframe() {
   const ID = "contentscript@tests.mozilla.org";
   let extensionData = {
     manifest: {
-      applications: {goanna: {id: ID}},
+      applications: {gecko: {id: ID}},
       content_scripts: [
         {
           "matches": ["http://mochi.test/*/file_sample.html"],
diff --git a/toolkit/components/extensions/test/mochitest/test_ext_runtime_id.html b/toolkit/components/extensions/test/mochitest/test_ext_runtime_id.html
index 2691a973b..4cdefda41 100644
--- a/toolkit/components/extensions/test/mochitest/test_ext_runtime_id.html
+++ b/toolkit/components/extensions/test/mochitest/test_ext_runtime_id.html
@@ -28,7 +28,7 @@ add_task(function* test_runtime_id() {
 
   let extension = ExtensionTestUtils.loadExtension({
     manifest: {
-      applications: {goanna: {id}},
+      applications: {gecko: {id}},
       "content_scripts": [{
         "matches": ["http://mochi.test/*/file_sample.html"],
         "run_at": "document_start",
diff --git a/toolkit/components/extensions/test/xpcshell/test_ext_experiments.js b/toolkit/components/extensions/test/xpcshell/test_ext_experiments.js
index 4138b0b75..ec660bdd5 100644
--- a/toolkit/components/extensions/test/xpcshell/test_ext_experiments.js
+++ b/toolkit/components/extensions/test/xpcshell/test_ext_experiments.js
@@ -84,7 +84,7 @@ add_task(function* test_experiments_api() {
 
   let addonFile = Extension.generateXPI({
     manifest: {
-      applications: {goanna: {id: "meh@web.extension"}},
+      applications: {gecko: {id: "meh@web.extension"}},
       permissions: ["experiments.meh"],
     },
 
@@ -104,7 +104,7 @@ add_task(function* test_experiments_api() {
 
   let boringAddonFile = Extension.generateXPI({
     manifest: {
-      applications: {goanna: {id: "boring@web.extension"}},
+      applications: {gecko: {id: "boring@web.extension"}},
     },
     background() {
       if (browser.meh) {
diff --git a/toolkit/components/extensions/test/xpcshell/test_ext_json_parser.js b/toolkit/components/extensions/test/xpcshell/test_ext_json_parser.js
index e3880848b..652f41315 100644
--- a/toolkit/components/extensions/test/xpcshell/test_ext_json_parser.js
+++ b/toolkit/components/extensions/test/xpcshell/test_ext_json_parser.js
@@ -9,7 +9,7 @@ add_task(function* test_json_parser() {
     files: {
       "manifest.json": String.raw`{
         // This is a manifest.
-        "applications": {"goanna": {"id": "${ID}"}},
+        "applications": {"gecko": {"id": "${ID}"}},
         "name": "This \" is // not a comment",
         "version": "0.1\\" // , "description": "This is not a description"
       }`,
@@ -17,7 +17,7 @@ add_task(function* test_json_parser() {
   });
 
   let expectedManifest = {
-    "applications": {"goanna": {"id": ID}},
+    "applications": {"gecko": {"id": ID}},
     "name": "This \" is // not a comment",
     "version": "0.1\\",
   };
diff --git a/toolkit/components/extensions/test/xpcshell/test_ext_legacy_extension_embedding.js b/toolkit/components/extensions/test/xpcshell/test_ext_legacy_extension_embedding.js
index abaa75383..5689ddfa7 100644
--- a/toolkit/components/extensions/test/xpcshell/test_ext_legacy_extension_embedding.js
+++ b/toolkit/components/extensions/test/xpcshell/test_ext_legacy_extension_embedding.js
@@ -41,7 +41,7 @@ add_task(function* test_embedded_webextension_utils() {
   // loaded from a 'webextension/' directory).
   let fakeHybridAddonFile = Extension.generateZipFile({
     "webextension/manifest.json": {
-      applications: {goanna: {id}},
+      applications: {gecko: {id}},
       name: "embedded webextension name",
       manifest_version: 2,
       version: "1.0",
diff --git a/toolkit/components/extensions/test/xpcshell/test_ext_localStorage.js b/toolkit/components/extensions/test/xpcshell/test_ext_localStorage.js
index ed750e0b5..0f0b41085 100644
--- a/toolkit/components/extensions/test/xpcshell/test_ext_localStorage.js
+++ b/toolkit/components/extensions/test/xpcshell/test_ext_localStorage.js
@@ -28,7 +28,7 @@ function backgroundScript() {
 
 const ID = "test-webextension@mozilla.com";
 let extensionData = {
-  manifest: {applications: {goanna: {id: ID}}},
+  manifest: {applications: {gecko: {id: ID}}},
   background: backgroundScript,
 };
 
diff --git a/toolkit/components/extensions/test/xpcshell/test_ext_management_uninstall_self.js b/toolkit/components/extensions/test/xpcshell/test_ext_management_uninstall_self.js
index d30ed0bb5..c82c9cd83 100644
--- a/toolkit/components/extensions/test/xpcshell/test_ext_management_uninstall_self.js
+++ b/toolkit/components/extensions/test/xpcshell/test_ext_management_uninstall_self.js
@@ -10,7 +10,7 @@ const id = "uninstall_self_test@tests.mozilla.com";
 
 const manifest = {
   applications: {
-    goanna: {
+    gecko: {
       id,
     },
   },
diff --git a/toolkit/components/extensions/test/xpcshell/test_ext_native_messaging.js b/toolkit/components/extensions/test/xpcshell/test_ext_native_messaging.js
index b7fb5aa64..5a6b628f5 100644
--- a/toolkit/components/extensions/test/xpcshell/test_ext_native_messaging.js
+++ b/toolkit/components/extensions/test/xpcshell/test_ext_native_messaging.js
@@ -88,7 +88,7 @@ add_task(function* test_happy_path() {
   let extension = ExtensionTestUtils.loadExtension({
     background,
     manifest: {
-      applications: {goanna: {id: ID}},
+      applications: {gecko: {id: ID}},
       permissions: ["nativeMessaging"],
     },
   });
@@ -157,7 +157,7 @@ if (AppConstants.platform == "win") {
     let extension = ExtensionTestUtils.loadExtension({
       background,
       manifest: {
-        applications: {goanna: {id: ID}},
+        applications: {gecko: {id: ID}},
         permissions: ["nativeMessaging"],
       },
     });
@@ -197,7 +197,7 @@ add_task(function* test_sendNativeMessage() {
   let extension = ExtensionTestUtils.loadExtension({
     background,
     manifest: {
-      applications: {goanna: {id: ID}},
+      applications: {gecko: {id: ID}},
       permissions: ["nativeMessaging"],
     },
   });
@@ -249,7 +249,7 @@ add_task(function* test_disconnect() {
   let extension = ExtensionTestUtils.loadExtension({
     background,
     manifest: {
-      applications: {goanna: {id: ID}},
+      applications: {gecko: {id: ID}},
       permissions: ["nativeMessaging"],
     },
   });
@@ -302,7 +302,7 @@ add_task(function* test_write_limit() {
   let extension = ExtensionTestUtils.loadExtension({
     background,
     manifest: {
-      applications: {goanna: {id: ID}},
+      applications: {gecko: {id: ID}},
       permissions: ["nativeMessaging"],
     },
   });
@@ -343,7 +343,7 @@ add_task(function* test_read_limit() {
   let extension = ExtensionTestUtils.loadExtension({
     background,
     manifest: {
-      applications: {goanna: {id: ID}},
+      applications: {gecko: {id: ID}},
       permissions: ["nativeMessaging"],
     },
   });
@@ -427,7 +427,7 @@ add_task(function* test_child_process() {
   let extension = ExtensionTestUtils.loadExtension({
     background,
     manifest: {
-      applications: {goanna: {id: ID}},
+      applications: {gecko: {id: ID}},
       permissions: ["nativeMessaging"],
     },
   });
@@ -459,7 +459,7 @@ add_task(function* test_stderr() {
     let extension = ExtensionTestUtils.loadExtension({
       background,
       manifest: {
-        applications: {goanna: {id: ID}},
+        applications: {gecko: {id: ID}},
         permissions: ["nativeMessaging"],
       },
     });
@@ -503,7 +503,7 @@ add_task(function* test_multiple_connects() {
   let extension = ExtensionTestUtils.loadExtension({
     background,
     manifest: {
-      applications: {goanna: {id: ID}},
+      applications: {gecko: {id: ID}},
       permissions: ["nativeMessaging"],
     },
   });
diff --git a/toolkit/components/extensions/test/xpcshell/test_ext_native_messaging_perf.js b/toolkit/components/extensions/test/xpcshell/test_ext_native_messaging_perf.js
index 2a86ef723..d3361fc70 100644
--- a/toolkit/components/extensions/test/xpcshell/test_ext_native_messaging_perf.js
+++ b/toolkit/components/extensions/test/xpcshell/test_ext_native_messaging_perf.js
@@ -108,7 +108,7 @@ add_task(function* test_round_trip_perf() {
       });
     },
     manifest: {
-      applications: {goanna: {id: ID}},
+      applications: {gecko: {id: ID}},
       permissions: ["nativeMessaging"],
     },
   });
diff --git a/toolkit/components/extensions/test/xpcshell/test_ext_native_messaging_unresponsive.js b/toolkit/components/extensions/test/xpcshell/test_ext_native_messaging_unresponsive.js
index 20f253e0e..a75a1d49d 100644
--- a/toolkit/components/extensions/test/xpcshell/test_ext_native_messaging_unresponsive.js
+++ b/toolkit/components/extensions/test/xpcshell/test_ext_native_messaging_unresponsive.js
@@ -62,7 +62,7 @@ add_task(function* test_unresponsive_native_app() {
   let extension = ExtensionTestUtils.loadExtension({
     background,
     manifest: {
-      applications: {goanna: {id: ID}},
+      applications: {gecko: {id: ID}},
       permissions: ["nativeMessaging"],
     },
   });
diff --git a/toolkit/components/extensions/test/xpcshell/test_ext_runtime_onInstalled_and_onStartup.js b/toolkit/components/extensions/test/xpcshell/test_ext_runtime_onInstalled_and_onStartup.js
index 563b981fa..a605eb4ea 100644
--- a/toolkit/components/extensions/test/xpcshell/test_ext_runtime_onInstalled_and_onStartup.js
+++ b/toolkit/components/extensions/test/xpcshell/test_ext_runtime_onInstalled_and_onStartup.js
@@ -99,7 +99,7 @@ add_task(function* test_should_fire_on_addon_update() {
     manifest: {
       "version": "1.0",
       "applications": {
-        "goanna": {
+        "gecko": {
           "id": EXTENSION_ID,
           "update_url": `http://localhost:${port}/test_update.json`,
         },
@@ -127,7 +127,7 @@ add_task(function* test_should_fire_on_addon_update() {
     manifest: {
       version: "2.0",
       applications: {
-        goanna: {
+        gecko: {
           id: EXTENSION_ID,
         },
       },
@@ -188,7 +188,7 @@ add_task(function* test_should_fire_on_browser_update() {
     manifest: {
       "version": "1.0",
       "applications": {
-        "goanna": {
+        "gecko": {
           "id": EXTENSION_ID,
         },
       },
@@ -264,7 +264,7 @@ add_task(function* test_should_not_fire_on_reload() {
     manifest: {
       "version": "1.0",
       "applications": {
-        "goanna": {
+        "gecko": {
           "id": EXTENSION_ID,
         },
       },
@@ -304,7 +304,7 @@ add_task(function* test_should_not_fire_on_restart() {
     manifest: {
       "version": "1.0",
       "applications": {
-        "goanna": {
+        "gecko": {
           "id": EXTENSION_ID,
         },
       },
diff --git a/toolkit/components/extensions/test/xpcshell/test_locale_data.js b/toolkit/components/extensions/test/xpcshell/test_locale_data.js
index 61d4dfeca..c3cd44e57 100644
--- a/toolkit/components/extensions/test/xpcshell/test_locale_data.js
+++ b/toolkit/components/extensions/test/xpcshell/test_locale_data.js
@@ -10,7 +10,7 @@ function* generateAddon(data) {
   let id = uuidGenerator.generateUUID().number;
 
   data = Object.assign({embedded: true}, data);
-  data.manifest = Object.assign({applications: {goanna: {id}}}, data.manifest);
+  data.manifest = Object.assign({applications: {gecko: {id}}}, data.manifest);
 
   let xpi = Extension.generateXPI(data);
   do_register_cleanup(() => {
diff --git a/toolkit/mozapps/extensions/internal/AddonTestUtils.jsm b/toolkit/mozapps/extensions/internal/AddonTestUtils.jsm
index d297d3267..ecfcb032b 100644
--- a/toolkit/mozapps/extensions/internal/AddonTestUtils.jsm
+++ b/toolkit/mozapps/extensions/internal/AddonTestUtils.jsm
@@ -422,7 +422,7 @@ var AddonTestUtils = {
 
     let manifest = yield body.json();
     try {
-      return manifest.applications.goanna.id;
+      return manifest.applications.gecko.id;
     } catch (e) {
       // IDs for WebExtensions are extracted from the certificate when
       // not present in the manifest, so just generate a random one.
diff --git a/toolkit/mozapps/extensions/internal/XPIProvider.jsm b/toolkit/mozapps/extensions/internal/XPIProvider.jsm
index a15732f46..7bf941ac2 100644
--- a/toolkit/mozapps/extensions/internal/XPIProvider.jsm
+++ b/toolkit/mozapps/extensions/internal/XPIProvider.jsm
@@ -938,8 +938,8 @@ var loadManifestFromWebManifest = Task.async(function*(aUri) {
   if (extension.errors.length)
     throw new Error("Extension is invalid");
 
-  let bss = (manifest.browser_specific_settings && manifest.browser_specific_settings.goanna)
-      || (manifest.applications && manifest.applications.goanna) || {};
+  let bss = (manifest.browser_specific_settings && manifest.browser_specific_settings.gecko)
+      || (manifest.applications && manifest.applications.gecko) || {};
   if (manifest.browser_specific_settings && manifest.applications) {
     logger.warn("Ignoring applications property in manifest");
   }
diff --git a/toolkit/mozapps/extensions/test/addons/test_delay_update_complete_webextension_v2/manifest.json b/toolkit/mozapps/extensions/test/addons/test_delay_update_complete_webextension_v2/manifest.json
index ae5d797dd..1a98f4660 100644
--- a/toolkit/mozapps/extensions/test/addons/test_delay_update_complete_webextension_v2/manifest.json
+++ b/toolkit/mozapps/extensions/test/addons/test_delay_update_complete_webextension_v2/manifest.json
@@ -3,7 +3,7 @@
   "name": "Delay Upgrade",
   "version": "2.0",
   "applications": {
-    "goanna": {
+    "gecko": {
       "id": "test_delay_update_complete_webext@tests.mozilla.org"
     }
   }
diff --git a/toolkit/mozapps/extensions/test/addons/test_delay_update_defer_webextension_v2/manifest.json b/toolkit/mozapps/extensions/test/addons/test_delay_update_defer_webextension_v2/manifest.json
index cd5ec5e9b..9561979dc 100644
--- a/toolkit/mozapps/extensions/test/addons/test_delay_update_defer_webextension_v2/manifest.json
+++ b/toolkit/mozapps/extensions/test/addons/test_delay_update_defer_webextension_v2/manifest.json
@@ -3,7 +3,7 @@
   "name": "Delay Upgrade",
   "version": "2.0",
   "applications": {
-    "goanna": {
+    "gecko": {
       "id": "test_delay_update_defer_webext@tests.mozilla.org"
     }
   }
diff --git a/toolkit/mozapps/extensions/test/addons/test_delay_update_ignore_webextension_v2/manifest.json b/toolkit/mozapps/extensions/test/addons/test_delay_update_ignore_webextension_v2/manifest.json
index 130d892a3..d9200ec11 100644
--- a/toolkit/mozapps/extensions/test/addons/test_delay_update_ignore_webextension_v2/manifest.json
+++ b/toolkit/mozapps/extensions/test/addons/test_delay_update_ignore_webextension_v2/manifest.json
@@ -3,7 +3,7 @@
   "name": "Delay Upgrade",
   "version": "2.0",
   "applications": {
-    "goanna": {
+    "gecko": {
       "id": "test_delay_update_ignore_webext@tests.mozilla.org"
     }
   }
diff --git a/toolkit/mozapps/extensions/test/addons/webextension_1/manifest.json b/toolkit/mozapps/extensions/test/addons/webextension_1/manifest.json
index a27e1e0f2..2ca5f40f7 100644
--- a/toolkit/mozapps/extensions/test/addons/webextension_1/manifest.json
+++ b/toolkit/mozapps/extensions/test/addons/webextension_1/manifest.json
@@ -3,7 +3,7 @@
   "version": "1.0",
   "manifest_version": 2,
   "applications": {
-    "goanna": {
+    "gecko": {
       "id": "webextension1@tests.mozilla.org"
     }
   },
diff --git a/toolkit/mozapps/extensions/test/addons/webextension_2/manifest.json b/toolkit/mozapps/extensions/test/addons/webextension_2/manifest.json
index 06ce26cd6..5b470d430 100644
--- a/toolkit/mozapps/extensions/test/addons/webextension_2/manifest.json
+++ b/toolkit/mozapps/extensions/test/addons/webextension_2/manifest.json
@@ -3,7 +3,7 @@
   "version": "1.0",
   "manifest_version": 2,
   "applications": {
-    "goanna": {
+    "gecko": {
       "id": "last-webextension2@tests.mozilla.org"
     }
   }
diff --git a/toolkit/mozapps/extensions/test/addons/webextension_3/manifest.json b/toolkit/mozapps/extensions/test/addons/webextension_3/manifest.json
index 0ea1066c8..b6ae6f10f 100644
--- a/toolkit/mozapps/extensions/test/addons/webextension_3/manifest.json
+++ b/toolkit/mozapps/extensions/test/addons/webextension_3/manifest.json
@@ -5,7 +5,7 @@
   "manifest_version": 2,
   "default_locale": "en",
   "applications": {
-    "goanna": {
+    "gecko": {
       "id": "webextension3@tests.mozilla.org"
     }
   }
diff --git a/toolkit/mozapps/extensions/test/browser/browser_inlinesettings_browser.js b/toolkit/mozapps/extensions/test/browser/browser_inlinesettings_browser.js
index e1cb7f579..199274628 100644
--- a/toolkit/mozapps/extensions/test/browser/browser_inlinesettings_browser.js
+++ b/toolkit/mozapps/extensions/test/browser/browser_inlinesettings_browser.js
@@ -17,7 +17,7 @@ function installAddon(details) {
   if (!details.manifest) {
     details.manifest = {};
   }
-  details.manifest.applications = {goanna: {id}};
+  details.manifest.applications = {gecko: {id}};
   let xpi = Extension.generateXPI(details);
 
   return AddonManager.installTemporaryAddon(xpi).then(addon => {
diff --git a/toolkit/mozapps/extensions/test/xpcshell/data/test_update.json b/toolkit/mozapps/extensions/test/xpcshell/data/test_update.json
index 5903019a3..027a9b233 100644
--- a/toolkit/mozapps/extensions/test/xpcshell/data/test_update.json
+++ b/toolkit/mozapps/extensions/test/xpcshell/data/test_update.json
@@ -5,7 +5,7 @@
         {
           "version": "1.0",
           "applications": {
-            "goanna": {
+            "gecko": {
               "strict_min_version": "1",
               "strict_min_version": "1"
             }
@@ -14,7 +14,7 @@
         {
           "version": "1.0",
           "applications": {
-            "goanna": {
+            "gecko": {
               "strict_min_version": "2",
               "strict_min_version": "2"
             }
@@ -25,7 +25,7 @@
           "update_link": "http://localhost:%PORT%/addons/test_update.xpi",
           "update_info_url": "http://example.com/updateInfo.xhtml",
           "applications": {
-            "goanna": {
+            "gecko": {
               "strict_min_version": "1",
               "strict_min_version": "1"
             }
@@ -39,7 +39,7 @@
         {
           "version": "1.0",
           "applications": {
-            "goanna": {
+            "gecko": {
               "strict_min_version": "0",
               "advisory_max_version": "1"
             }
@@ -53,7 +53,7 @@
         {
           "version": "1.0",
           "applications": {
-            "goanna": {
+            "gecko": {
               "strict_min_version": "0",
               "advisory_max_version": "1"
             }
@@ -67,7 +67,7 @@
         {
           "version": "1.0",
           "applications": {
-            "goanna": {
+            "gecko": {
               "strict_min_version": "3",
               "advisory_max_version": "3"
             }
@@ -81,7 +81,7 @@
         {
           "version": "5.0",
           "applications": {
-            "goanna": {
+            "gecko": {
               "strict_min_version": "0",
               "advisory_max_version": "0"
             }
@@ -95,7 +95,7 @@
         {
           "version": "1.0",
           "applications": {
-            "goanna": {
+            "gecko": {
               "strict_min_version": "0",
               "advisory_max_version": "1"
             }
@@ -110,7 +110,7 @@
           "version": "2.0",
           "update_link": "http://localhost:%PORT%/addons/test_update8.xpi",
           "applications": {
-            "goanna": {
+            "gecko": {
               "strict_min_version": "1",
               "advisory_max_version": "1"
             }
@@ -125,7 +125,7 @@
           "version": "2.0",
           "update_link": "http://localhost:%PORT%/addons/test_update9_2.xpi",
           "applications": {
-            "goanna": {
+            "gecko": {
               "strict_min_version": "1",
               "advisory_max_version": "1"
             }
@@ -136,7 +136,7 @@
           "version": "3.0",
           "update_link": "http://localhost:%PORT%/addons/test_update9_3.xpi",
           "applications": {
-            "goanna": {
+            "gecko": {
               "strict_min_version": "0.9",
               "advisory_max_version": "0.9"
             }
@@ -147,7 +147,7 @@
           "version": "4.0",
           "update_link": "http://localhost:%PORT%/addons/test_update9_4.xpi",
           "applications": {
-            "goanna": {
+            "gecko": {
               "strict_min_version": "0.9",
               "advisory_max_version": "0.9"
             }
@@ -158,7 +158,7 @@
           "version": "4.0",
           "update_link": "http://localhost:%PORT%/addons/test_update9_5.xpi",
           "applications": {
-            "goanna": {
+            "gecko": {
               "strict_min_version": "5",
               "advisory_max_version": "6"
             }
@@ -173,7 +173,7 @@
           "version": "1.0",
           "update_link": "http://localhost:%PORT%/addons/test_update10.xpi",
           "applications": {
-            "goanna": {
+            "gecko": {
               "strict_min_version": "0.1",
               "advisory_max_version": "0.4"
             }
@@ -188,7 +188,7 @@
           "version": "2.0",
           "update_link": "http://localhost:%PORT%/addons/test_update11.xpi",
           "applications": {
-            "goanna": {
+            "gecko": {
               "strict_min_version": "0.1",
               "strict_max_version": "0.2"
             }
@@ -203,7 +203,7 @@
           "version": "2.0",
           "update_link": "http://localhost:%PORT%/addons/test_update12.xpi",
           "applications": {
-            "goanna": {
+            "gecko": {
               "strict_min_version": "1",
               "advisory_max_version": "1"
             }
diff --git a/toolkit/mozapps/extensions/test/xpcshell/data/test_updatecheck.json b/toolkit/mozapps/extensions/test/xpcshell/data/test_updatecheck.json
index 1861db8cc..811e50158 100644
--- a/toolkit/mozapps/extensions/test/xpcshell/data/test_updatecheck.json
+++ b/toolkit/mozapps/extensions/test/xpcshell/data/test_updatecheck.json
@@ -6,7 +6,7 @@
           "version": "1.0",
           "update_link": "https://localhost:4444/addons/test1.xpi",
           "applications": {
-            "goanna": {
+            "gecko": {
               "strict_min_version": "1",
               "strict_max_version": "1"
             }
@@ -17,7 +17,7 @@
           "version": "2.0",
           "update_link": "https://localhost:4444/addons/test2.xpi",
           "applications": {
-            "goanna": {
+            "gecko": {
               "strict_min_version": "2",
               "strict_max_version": "2"
             }
@@ -27,7 +27,7 @@
           "version": "3.0",
           "update_link": "https://localhost:4444/addons/test3.xpi",
           "applications": {
-            "goanna": {
+            "gecko": {
               "strict_min_version": "1",
               "strict_max_version": "1"
             }
@@ -37,7 +37,7 @@
           "version": "2.0",
           "update_link": "https://localhost:4444/addons/test2.xpi",
           "applications": {
-            "goanna": {
+            "gecko": {
               "strict_min_version": "1",
               "strict_max_version": "2"
             }
@@ -48,7 +48,7 @@
           "version": "4.0",
           "update_link": "https://localhost:4444/addons/test4.xpi",
           "applications": {
-            "goanna": {
+            "gecko": {
               "strict_min_version": "2",
               "strict_max_version": "2"
             }
@@ -68,7 +68,7 @@
           "version": "2.0",
           "update_link": "http://localhost:4444/broken.xpi",
           "applications": {
-            "goanna": {
+            "gecko": {
               "strict_min_version": "1",
               "strict_max_version": "1"
              }
@@ -83,7 +83,7 @@
           "version": "2.0",
           "update_link": "http://localhost:4444/broken.xpi",
           "applications": {
-            "goanna": {
+            "gecko": {
               "strict_min_version": "1",
               "strict_max_version": "1"
              }
@@ -103,7 +103,7 @@
           "version": "2.0",
           "update_link": "http://localhost:4444/broken.xpi",
           "applications": {
-            "goanna": {
+            "gecko": {
               "strict_min_version": "1",
               "strict_max_version": "2"
             }
@@ -121,7 +121,7 @@
           "version": "2.0",
           "update_link": "http://localhost:4444/broken.xpi",
           "applications": {
-            "goanna": {
+            "gecko": {
               "strict_min_version": "1",
               "strict_max_version": "1"
             }
@@ -139,7 +139,7 @@
           "update_link": "http://localhost:4444/broken.xpi",
           "update_hash": "sha256:78fc1d2887eda35b4ad2e3a0b60120ca271ce6e6",
           "applications": {
-            "goanna": {
+            "gecko": {
               "strict_min_version": "1",
               "strict_max_version": "1"
             }
@@ -156,7 +156,7 @@
           "version": "2.0",
           "update_link": "https://localhost:4444/broken.xpi",
           "applications": {
-            "goanna": {
+            "gecko": {
               "strict_min_version": "1",
               "strict_max_version": "1"
             }
@@ -173,7 +173,7 @@
           "version": "2.0",
           "update_link": "https://localhost:4444/broken.xpi",
           "applications": {
-            "goanna": {
+            "gecko": {
               "strict_min_version": "1",
               "strict_max_version": "1"
             }
@@ -192,7 +192,7 @@
           "update_link": "http://localhost:4444/broken.xpi",
           "update_hash": "sha1:78fc1d2887eda35b4ad2e3a0b60120ca271ce6e6",
           "applications": {
-            "goanna": {
+            "gecko": {
               "strict_min_version": "1",
               "strict_max_version": "1"
             }
@@ -211,7 +211,7 @@
           "update_link": "https://localhost:4444/broken.xpi",
           "update_hash": "sha1:78fc1d2887eda35b4ad2e3a0b60120ca271ce6e6",
           "applications": {
-            "goanna": {
+            "gecko": {
               "strict_min_version": "1",
               "strict_max_version": "1"
             }
@@ -236,7 +236,7 @@
           "version": "1.0",
           "update_link": "https://localhost:4444/addons/test1.xpi",
           "applications": {
-            "goanna": {
+            "gecko": {
               "strict_min_version": "0.1",
               "advisory_max_version": "0.2"
             }
@@ -246,7 +246,7 @@
           "version": "2.0",
           "update_link": "https://localhost:4444/addons/test2.xpi",
           "applications": {
-            "goanna": {
+            "gecko": {
               "strict_min_version": "0.5",
               "advisory_max_version": "0.6"
             }
@@ -257,7 +257,7 @@
           "version": "3.0",
           "update_link": "https://localhost:4444/addons/test3.xpi",
           "applications": {
-            "goanna": {
+            "gecko": {
               "strict_min_version": "2",
               "advisory_max_version": "3"
             }
@@ -275,7 +275,7 @@
           "version": "1.0",
           "update_link": "https://localhost:4444/addons/test1.xpi",
           "applications": {
-            "goanna": {
+            "gecko": {
               "strict_min_version": "0.1",
               "advisory_max_version": "0.2"
             }
@@ -286,7 +286,7 @@
           "version": "2.0",
           "update_link": "https://localhost:4444/addons/test2.xpi",
           "applications": {
-            "goanna": {
+            "gecko": {
               "strict_min_version": "0.5",
               "advisory_max_version": "0.6"
             }
@@ -297,7 +297,7 @@
           "version": "3.0",
           "update_link": "https://localhost:4444/addons/test3.xpi",
           "applications": {
-            "goanna": {
+            "gecko": {
               "strict_min_version": "2",
               "advisory_max_version": "3"
             }
@@ -315,7 +315,7 @@
           "update_link": "https://localhost:4444/addons/test1.xpi",
           "_comment_": "strictCompatibility: true",
           "applications": {
-            "goanna": {
+            "gecko": {
               "strict_min_version": "0.1",
               "strict_max_version": "0.2"
             }
diff --git a/toolkit/mozapps/extensions/test/xpcshell/head_addons.js b/toolkit/mozapps/extensions/test/xpcshell/head_addons.js
index 5d0c6820b..756ef8329 100644
--- a/toolkit/mozapps/extensions/test/xpcshell/head_addons.js
+++ b/toolkit/mozapps/extensions/test/xpcshell/head_addons.js
@@ -747,7 +747,7 @@ function writeInstallRDFForExtension(aData, aDir, aId, aExtraFile) {
  *          An optional string to override the default installation aId
  * @return  A file pointing to where the extension was installed
  */
-function promiseWriteWebManifestForExtension(aData, aDir, aId = aData.applications.goanna.id) {
+function promiseWriteWebManifestForExtension(aData, aDir, aId = aData.applications.gecko.id) {
   let files = {
     "manifest.json": JSON.stringify(aData),
   }
diff --git a/toolkit/mozapps/extensions/test/xpcshell/test_delay_update_webextension.js b/toolkit/mozapps/extensions/test/xpcshell/test_delay_update_webextension.js
index b9b497334..83e55f57d 100644
--- a/toolkit/mozapps/extensions/test/xpcshell/test_delay_update_webextension.js
+++ b/toolkit/mozapps/extensions/test/xpcshell/test_delay_update_webextension.js
@@ -52,7 +52,7 @@ add_task(function* delay_updates_ignore() {
     manifest: {
       "version": "1.0",
       "applications": {
-        "goanna": {
+        "gecko": {
           "id": IGNORE_ID,
           "update_url": `http://localhost:${gPort}/data/test_delay_updates_ignore.json`,
         },
@@ -132,7 +132,7 @@ add_task(function* delay_updates_complete() {
     manifest: {
       "version": "1.0",
       "applications": {
-        "goanna": {
+        "gecko": {
           "id": COMPLETE_ID,
           "update_url": `http://localhost:${gPort}/data/test_delay_updates_complete.json`,
         },
@@ -196,7 +196,7 @@ add_task(function* delay_updates_defer() {
     manifest: {
       "version": "1.0",
       "applications": {
-        "goanna": {
+        "gecko": {
           "id": DEFER_ID,
           "update_url": `http://localhost:${gPort}/data/test_delay_updates_defer.json`,
         },
@@ -293,7 +293,7 @@ add_task(function* runtime_reload() {
     manifest: {
       "version": "1.0",
       "applications": {
-        "goanna": {
+        "gecko": {
           "id": NOUPDATE_ID,
           "update_url": `http://localhost:${gPort}/data/test_no_update.json`,
         },
diff --git a/toolkit/mozapps/extensions/test/xpcshell/test_ext_management.js b/toolkit/mozapps/extensions/test/xpcshell/test_ext_management.js
index f5304a080..a3b3f477c 100644
--- a/toolkit/mozapps/extensions/test/xpcshell/test_ext_management.js
+++ b/toolkit/mozapps/extensions/test/xpcshell/test_ext_management.js
@@ -23,7 +23,7 @@ add_task(function* test_management_get_self_complete() {
 
   let manifest = {
     applications: {
-      goanna: {
+      gecko: {
         id,
         update_url: "https://updates.mozilla.com/",
       },
@@ -60,7 +60,7 @@ add_task(function* test_management_get_self_complete() {
   equal(extInfo.mayDisable, true, "getSelf returned the expected value for mayDisable");
   equal(extInfo.enabled, true, "getSelf returned the expected value for enabled");
   equal(extInfo.homepageUrl, manifest.homepage_url, "getSelf returned the expected homepageUrl");
-  equal(extInfo.updateUrl, manifest.applications.goanna.update_url, "getSelf returned the expected updateUrl");
+  equal(extInfo.updateUrl, manifest.applications.gecko.update_url, "getSelf returned the expected updateUrl");
   ok(extInfo.optionsUrl.endsWith(manifest.options_ui.page), "getSelf returned the expected optionsUrl");
   for (let [index, size] of Object.keys(manifest.icons).sort().entries()) {
     equal(extInfo.icons[index].size, +size, "getSelf returned the expected icon size");
@@ -77,7 +77,7 @@ add_task(function* test_management_get_self_minimal() {
 
   let manifest = {
     applications: {
-      goanna: {
+      gecko: {
         id,
       },
     },
@@ -115,7 +115,7 @@ add_task(function* test_management_get_self_permanent() {
 
   let manifest = {
     applications: {
-      goanna: {
+      gecko: {
         id,
       },
     },
diff --git a/toolkit/mozapps/extensions/test/xpcshell/test_json_updatecheck.js b/toolkit/mozapps/extensions/test/xpcshell/test_json_updatecheck.js
index 6defb1946..a0f874332 100644
--- a/toolkit/mozapps/extensions/test/xpcshell/test_json_updatecheck.js
+++ b/toolkit/mozapps/extensions/test/xpcshell/test_json_updatecheck.js
@@ -103,8 +103,8 @@ add_task(function* test_default_values() {
   equal(update.updateInfoURL, null, "updateInfoURL");
 
   // If there's no applications property, we default to using one
-  // containing "goanna". If there is an applications property, but
-  // it doesn't contain "goanna", the update is skipped.
+  // containing "gecko". If there is an applications property, but
+  // it doesn't contain "gecko", the update is skipped.
   updates = yield checkUpdates({
     id: "updatecheck-defaults@tests.mozilla.org",
     version: "0.1",
@@ -140,7 +140,7 @@ add_task(function* test_explicit_values() {
       update_info_url: "https://example.com/update_info.html",
       multiprocess_compatible: false,
       applications: {
-        goanna: {
+        gecko: {
           strict_min_version: "42.0a2.xpcshell",
           strict_max_version: "43.xpcshell"
         }
@@ -220,13 +220,13 @@ add_task(function* test_strict_compat() {
       version: "0.1",
       updates: [
         { version: "0.2",
-          applications: { goanna: { strict_max_version: "*" } } },
+          applications: { gecko: { strict_max_version: "*" } } },
         { version: "0.3",
-          applications: { goanna: { strict_max_version: "43" } } },
+          applications: { gecko: { strict_max_version: "43" } } },
         { version: "0.4",
-          applications: { goanna: { advisory_max_version: "43" } } },
+          applications: { gecko: { advisory_max_version: "43" } } },
         { version: "0.5",
-          applications: { goanna: { advisory_max_version: "43",
+          applications: { gecko: { advisory_max_version: "43",
                                    strict_max_version: "44" } } },
       ]
     });
diff --git a/toolkit/mozapps/extensions/test/xpcshell/test_reload.js b/toolkit/mozapps/extensions/test/xpcshell/test_reload.js
index 1a8da9827..5873d1980 100644
--- a/toolkit/mozapps/extensions/test/xpcshell/test_reload.js
+++ b/toolkit/mozapps/extensions/test/xpcshell/test_reload.js
@@ -135,7 +135,7 @@ add_task(function* test_reload_to_invalid_version_fails() {
     manifest_version: 2,
     version: "1.0",
     applications: {
-      goanna: {
+      gecko: {
         id: addonId,
       }
     },
@@ -154,8 +154,8 @@ add_task(function* test_reload_to_invalid_version_fails() {
   addonDir.remove(true);
 
   // update the manifest to make the add-on version incompatible, so the reload will reject
-  manifest.applications.goanna.strict_min_version = "1";
-  manifest.applications.goanna.strict_max_version = "1";
+  manifest.applications.gecko.strict_min_version = "1";
+  manifest.applications.gecko.strict_max_version = "1";
   manifest.version = "2.0";
 
   addonDir = yield promiseWriteWebManifestForExtension(manifest, tempdir, "invalid_version", false);
diff --git a/toolkit/mozapps/extensions/test/xpcshell/test_temporary.js b/toolkit/mozapps/extensions/test/xpcshell/test_temporary.js
index 0b20bb7ca..5172e6954 100644
--- a/toolkit/mozapps/extensions/test/xpcshell/test_temporary.js
+++ b/toolkit/mozapps/extensions/test/xpcshell/test_temporary.js
@@ -256,7 +256,7 @@ add_task(function*() {
         version: "4.0",
         name: "Test WebExtension 1 (temporary)",
         applications: {
-          goanna: {
+          gecko: {
             id: ID
           }
         }
@@ -286,7 +286,7 @@ add_task(function*() {
         version: "5.0",
         name: "Test WebExtension 1 (temporary)",
         applications: {
-          goanna: {
+          gecko: {
             id: ID
           }
         }
diff --git a/toolkit/mozapps/extensions/test/xpcshell/test_update_webextensions.js b/toolkit/mozapps/extensions/test/xpcshell/test_update_webextensions.js
index 7c41efdf0..3941f9ea1 100644
--- a/toolkit/mozapps/extensions/test/xpcshell/test_update_webextensions.js
+++ b/toolkit/mozapps/extensions/test/xpcshell/test_update_webextensions.js
@@ -63,7 +63,7 @@ var checkUpdates = Task.async(function* (aData, aReason = AddonManager.UPDATE_WH
 
   let id = uuidGenerator.generateUUID().number;
   provide(aData, "addon.id", id);
-  provide(aData, "addon.manifest.applications.goanna.id", id);
+  provide(aData, "addon.manifest.applications.gecko.id", id);
 
   let updatePath = `/updates/${id}.json`.replace(/[{}]/g, "");
   let updateUrl = `http://localhost:${gPort}${updatePath}`
@@ -74,7 +74,7 @@ var checkUpdates = Task.async(function* (aData, aReason = AddonManager.UPDATE_WH
   };
 
 
-  provide(aData, "addon.manifest.applications.goanna.update_url", updateUrl);
+  provide(aData, "addon.manifest.applications.gecko.update_url", updateUrl);
   let awaitInstall = promiseInstallWebExtension(aData.addon);
 
 
@@ -83,7 +83,7 @@ var checkUpdates = Task.async(function* (aData, aReason = AddonManager.UPDATE_WH
     update.version = version;
 
     provide(update, "addon.id", id);
-    provide(update, "addon.manifest.applications.goanna.id", id);
+    provide(update, "addon.manifest.applications.gecko.id", id);
     let addon = update.addon;
 
     delete update.addon;
@@ -137,12 +137,12 @@ add_task(function* checkUpdateMetadata() {
     addon: {
       manifest: {
         version: "1.0",
-        applications: { goanna: { strict_max_version: "45" } },
+        applications: { gecko: { strict_max_version: "45" } },
       }
     },
     updates: {
       "1.0": {
-        applications: { goanna: { strict_min_version: "40",
+        applications: { gecko: { strict_min_version: "40",
                                  strict_max_version: "48" } },
       }
     }
@@ -166,7 +166,7 @@ add_task(function* checkUpdateToWebExt() {
     updates: {
       "1.1": { },
       "1.2": { },
-      "1.3": { "applications": { "goanna": { "strict_min_version": "48" } } },
+      "1.3": { "applications": { "gecko": { "strict_min_version": "48" } } },
     }
   });
 
@@ -228,7 +228,7 @@ add_task(function* checkIllegalUpdateURL() {
   for (let url of URLS) {
     let { messages } = yield promiseConsoleOutput(() => {
       let addonFile = createTempWebExtensionFile({
-        manifest: { applications: { goanna: { update_url: url } } },
+        manifest: { applications: { gecko: { update_url: url } } },
       });
 
       return AddonManager.getInstallForFile(addonFile).then(install => {
diff --git a/toolkit/mozapps/extensions/test/xpcshell/test_webextension.js b/toolkit/mozapps/extensions/test/xpcshell/test_webextension.js
index 74ff0a225..ec5242b7e 100644
--- a/toolkit/mozapps/extensions/test/xpcshell/test_webextension.js
+++ b/toolkit/mozapps/extensions/test/xpcshell/test_webextension.js
@@ -128,7 +128,7 @@ add_task(function*() {
     version: "1.0",
     manifest_version: 2,
     applications: {
-      goanna: {
+      gecko: {
         id: ID
       }
     }
@@ -193,7 +193,7 @@ add_task(function*() {
     name: "Web Extension Name",
     manifest_version: 2,
     applications: {
-      goanna: {
+      gecko: {
         id: ID
       }
     }
@@ -217,7 +217,7 @@ add_task(function*() {
     version: "1.0",
     manifest_version: 1,
     applications: {
-      goanna: {
+      gecko: {
         id: ID
       }
     }
@@ -264,7 +264,7 @@ add_task(function* test_options_ui() {
   const extensionId = "webextension@tests.mozilla.org";
   yield promiseInstallWebExtension({
     manifest: {
-      applications: {goanna: {id: extensionId}},
+      applications: {gecko: {id: extensionId}},
       "options_ui": {
         "page": "options.html",
       },
@@ -283,7 +283,7 @@ add_task(function* test_options_ui() {
   const ID2 = "webextension2@tests.mozilla.org";
   yield promiseInstallWebExtension({
     manifest: {
-      applications: {goanna: {id: ID2}},
+      applications: {gecko: {id: ID2}},
       "options_ui": {
         "page": "options.html",
         "open_in_tab": true,
@@ -309,7 +309,7 @@ add_task(function* test_experiments_dependencies() {
 
   let addonFile = createTempWebExtensionFile({
     manifest: {
-      applications: {goanna: {id: "meh@experiment"}},
+      applications: {gecko: {id: "meh@experiment"}},
       "permissions": ["experiments.meh"],
     },
   });
diff --git a/toolkit/mozapps/extensions/test/xpcshell/test_webextension_icons.js b/toolkit/mozapps/extensions/test/xpcshell/test_webextension_icons.js
index 09e626589..d44fd480d 100644
--- a/toolkit/mozapps/extensions/test/xpcshell/test_webextension_icons.js
+++ b/toolkit/mozapps/extensions/test/xpcshell/test_webextension_icons.js
@@ -31,7 +31,7 @@ add_task(function*() {
     version: "1.0",
     manifest_version: 2,
     applications: {
-      goanna: {
+      gecko: {
         id: ID
       }
     },
@@ -95,7 +95,7 @@ add_task(function*() {
     version: "1.0",
     manifest_version: 2,
     applications: {
-      goanna: {
+      gecko: {
         id: ID
       }
     },
@@ -141,7 +141,7 @@ add_task(function*() {
     version: "1.0",
     manifest_version: 2,
     applications: {
-      goanna: {
+      gecko: {
         id: ID
       }
     }
diff --git a/toolkit/mozapps/extensions/test/xpcshell/test_webextension_install.js b/toolkit/mozapps/extensions/test/xpcshell/test_webextension_install.js
index 5c5862543..36b78183c 100644
--- a/toolkit/mozapps/extensions/test/xpcshell/test_webextension_install.js
+++ b/toolkit/mozapps/extensions/test/xpcshell/test_webextension_install.js
@@ -145,7 +145,7 @@ add_task(function* test_bss_id() {
     version: "1.0",
 
     browser_specific_settings: {
-      goanna: {
+      gecko: {
         id: ID
       }
     }
@@ -179,13 +179,13 @@ add_task(function* test_two_ids() {
     version: "1.0",
 
     applications: {
-      goanna: {
+      gecko: {
         id: BAD_ID
       }
     },
 
     browser_specific_settings: {
-      goanna: {
+      gecko: {
         id: GOOD_ID
       }
     }
@@ -220,7 +220,7 @@ add_task(function* test_strict_min_max() {
   // bad max good min
   let apps = {
     applications: {
-      goanna: {
+      gecko: {
         id: addonId,
         strict_min_version: "1",
         strict_max_version: "1"
@@ -246,7 +246,7 @@ add_task(function* test_strict_min_max() {
   // bad min good max
   apps = {
     applications: {
-      goanna: {
+      gecko: {
         id: addonId,
         strict_min_version: "2",
         strict_max_version: "2"
@@ -272,7 +272,7 @@ add_task(function* test_strict_min_max() {
   // bad both
   apps = {
     applications: {
-      goanna: {
+      gecko: {
         id: addonId,
         strict_min_version: "2",
         strict_max_version: "1"
@@ -298,7 +298,7 @@ add_task(function* test_strict_min_max() {
   // bad only min
   apps = {
     applications: {
-      goanna: {
+      gecko: {
         id: addonId,
         strict_min_version: "2"
       },
@@ -323,7 +323,7 @@ add_task(function* test_strict_min_max() {
   // bad only max
   apps = {
     applications: {
-      goanna: {
+      gecko: {
         id: addonId,
         strict_max_version: "1"
       },
@@ -348,7 +348,7 @@ add_task(function* test_strict_min_max() {
   // good both
   apps = {
     applications: {
-      goanna: {
+      gecko: {
         id: addonId,
         strict_min_version: "1",
         strict_max_version: "2"
@@ -373,7 +373,7 @@ add_task(function* test_strict_min_max() {
   let newId = "strict_min_only@tests.mozilla.org";
   apps = {
     applications: {
-      goanna: {
+      gecko: {
         id: newId,
         strict_min_version: "1",
       },
@@ -398,7 +398,7 @@ add_task(function* test_strict_min_max() {
   newId = "strict_max_only@tests.mozilla.org";
   apps = {
     applications: {
-      goanna: {
+      gecko: {
         id: newId,
         strict_max_version: "2",
       },
@@ -424,7 +424,7 @@ add_task(function* test_strict_min_max() {
     newId = "strict_min_star@tests.mozilla.org";
     let minStarApps = {
       applications: {
-        goanna: {
+        gecko: {
           id: newId,
           strict_min_version: version,
         },
@@ -451,7 +451,7 @@ add_task(function* test_strict_min_max() {
   newId = "checkCompatibility@tests.mozilla.org";
   apps = {
     applications: {
-      goanna: {
+      gecko: {
         id: newId,
         strict_max_version: "1",
       },
diff --git a/toolkit/mozapps/extensions/test/xpcshell/test_webextension_paths.js b/toolkit/mozapps/extensions/test/xpcshell/test_webextension_paths.js
index a85f9d0b5..29a3dacf7 100644
--- a/toolkit/mozapps/extensions/test/xpcshell/test_webextension_paths.js
+++ b/toolkit/mozapps/extensions/test/xpcshell/test_webextension_paths.js
@@ -24,7 +24,7 @@ add_task(function* test_bad_unpacked_path() {
     version: "1.0",
 
     browser_specific_settings: {
-      goanna: {
+      gecko: {
         id: MANIFEST_ID
       }
     }