Argument has invalid value, please run info:language:list for list of available locale
Von Miro Kodet
Static content deploy fails with missing locale
This issue appears mostly in Docker containers after initial build. If you try to run bin/magento setup:static-content:deploy you will get an error like this:
Argument has invalid value, please run info:language:list for list of available locale
The list of possible locales in Magento 2 is driven by options provided by ICU library/package. The ICU project homepage is https://icu.unicode.org/.
If you run your environment based on Alpine Linux, you will need to install icu packages. This will provide the necessary locales.
apk add icu-dev icu-libs icu-data-full
After that, you can run bin/magento setup:static-content:deploy and it should work.