点击vscode插件 --> 点击3个点 --> 选择从VSIX安装

点击更新报
Cannot update while running on a read-only volume. The application is on a read-only volume. Please move the application and try again. If you’re on macOS Sierra or later, you’ll need to move the application out of the Downloads directory. This might mean the application was put on quarantine by macOS. See this link for more information.

在只读卷上无法进行更新。该应用程序位于只读卷上。请移动应用程序并重试。如果您使用的是 macOS Sierra 或更高版本，则需要将应用程序移出下载目录。这可能意味着应用程序被 macOS 隔离了。有关更多信息，请参阅此链接。

mac把下载的vscode移动到Application里面，就可以检查更新了

更新失败了，算了还是直接去官网重新下载一下吧。