今天在 Ubuntu 执行 apt-get update 时得到了下面这个错误：
....
Get:9 https://dl.yarnpkg.com/debian stable InRelease [17.1 kB]
Err:9 https://dl.yarnpkg.com/debian stable InReleaseThe following signatures were invalid: EXPKEYSIG 23E7166788B63E1E Yarn Packaging <yarn@dan.cx>
....
W: GPG error: https://dl.yarnpkg.com/debian stable InRelease: The following signatures were invalid: EXPKEYSIG 23E7166788B63E1E Yarn Packaging <yarn@dan.cx>
E: The repository 'https://dl.yarnpkg.com/debian stable InRelease' is not signed.
N: Updating from such a repository can't be done securely, and is therefore disabled by default.
N: See apt-secure(8) manpage for repository creation and user configuration details.
....
国内搜索到的没搜索到适用于我的解决方案。。后来在国外找到适合我的解决方案
curl -sS https://dl.yarnpkg.com/debian/pubkey.gpg | sudo apt-key add -
原贴：https://github.com/yarnpkg/yarn/issues/6885
另外题外话吐槽 CSDN 发帖居然只有：原创、转载、翻译，其中除了原创之外居然都需要勾选：“原文允许翻译或者本次翻译已经获得原文作者授权”，当然没得到授权啦，，这是整理罢了。。所以就不能来个符合的分类？？？