- l10n: Add Chinese (simplified) extension locales (Thanks, @enlove!)

- Linting (ESLint): Avoid reporting `no-console`
- Refactoring: Avoid Firefox console errors with hidden iframe
- Docs (CHANGES): Fix Markdown heading level

editor/extensions/ext-locale/foreignobject/zh-CN.js

@@ -0,0 +1,25 @@
+export default {
+  name: '外部对象',
+  buttons: [
+    {
+      title: '外部对象工具'
+    },
+    {
+      title: '编辑外部对象内容'
+    }
+  ],
+  contextTools: [
+    {
+      title: '改变外部对象宽度',
+      label: 'w'
+    },
+    {
+      title: '改变外部对象高度',
+      label: 'h'
+    },
+    {
+      title: '改变外部对象文字大小',
+      label: '文字大小'
+    }
+  ]
+};