diff --git a/spec/api-browser-window-spec.js b/spec/api-browser-window-spec.js
index bad3b80a9b5c..cf3442d59ce4 100644
--- a/spec/api-browser-window-spec.js
+++ b/spec/api-browser-window-spec.js
@@ -865,6 +865,7 @@ describe('browser-window module', function () {
           ipcMain.once('answer', function (event, message) {
             assert.equal(message.runtimeId, 'foo')
             assert.equal(message.tabId, w.webContents.id)
+            assert.equal(message.i18nString, 'foo - bar (baz)')
             done()
           })
         })
diff --git a/spec/fixtures/devtools-extensions/foo/_locales/en/messages.json b/spec/fixtures/devtools-extensions/foo/_locales/en/messages.json
new file mode 100644
index 000000000000..fe5653c2b411
--- /dev/null
+++ b/spec/fixtures/devtools-extensions/foo/_locales/en/messages.json
@@ -0,0 +1,10 @@
+{
+  "foo": {
+    "message": "foo - $BAZ$ ($2)",
+    "placeholders": {
+      "baz": {
+        "content": "$1"
+      }
+    }
+  }
+}
diff --git a/spec/fixtures/devtools-extensions/foo/index.html b/spec/fixtures/devtools-extensions/foo/index.html
index 2e0a29aff3d0..414370ae2c06 100644
--- a/spec/fixtures/devtools-extensions/foo/index.html
+++ b/spec/fixtures/devtools-extensions/foo/index.html
@@ -6,7 +6,8 @@
     <script>
       var message = JSON.stringify({
         runtimeId: chrome.runtime.id,
-        tabId: chrome.devtools.inspectedWindow.tabId
+        tabId: chrome.devtools.inspectedWindow.tabId,
+        i18nString: chrome.i18n.getMessage('foo', ['bar', 'baz'])
       })
       var sendMessage = `require('electron').ipcRenderer.send('answer', ${message})`
       window.chrome.devtools.inspectedWindow.eval(sendMessage, function () {})
diff --git a/spec/fixtures/devtools-extensions/foo/manifest.json b/spec/fixtures/devtools-extensions/foo/manifest.json
index 413853e8d351..b88ab65a1ea8 100644
--- a/spec/fixtures/devtools-extensions/foo/manifest.json
+++ b/spec/fixtures/devtools-extensions/foo/manifest.json
@@ -1,5 +1,6 @@
 {
   "name": "foo",
   "version": "1.0",
-  "devtools_page": "foo.html"
+  "devtools_page": "foo.html",
+  "default_locale": "en"
 }