浏览器的导航工具栏可以完全隐藏，这样就只剩标签栏、菜单栏和内容区域了。

The browser navigation toolbar can be completely hidden, leaving only the TAB bar, menu button, and content area.

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在火狐全屏模式时，工具栏和标签页会在屏幕上部隐藏，只有当鼠标移上去是才显示。

In Firefox’s fullscreen mode, toolbars and the tab strip are hiddenat the top of the screen and only shown on mouseover.

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要测试这个隐藏导航栏，您得在about： flags面板里启动这一特性并从标签的环境菜单里进行切换。

To test the new hidden navigation bar, you have to enable the feature from the about: flags panel and then toggle it from the TAB context menu.

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