I am running Magento 2.2.1 on my website. I noticed I could not access my site. I went the folder and noticed app folder is gone. How I get this back?
Do you or your host have any backups that you can use to restore?
I guess its not missing, you just installed your system via composer with use vendor folder settings and all your /app/code files are in /vendor folder, just have a look into /vendor/magento ..
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