I see.
In v2, a web archive is recognized by the following:
1. end with ."war" suffix
Or
2. contains WEB-INF/web.xml or WEB-INF/sun-web.xml
In your case, the contents of the archive do not contain WEB-INF/web.xml or WEB-INF/sun-web.xml. So when it's deployed as .war file, it can be recognized as a web archive with the suffix and when it's deployed as a directory, it cannot be recognized.
You need to put a WEB-INF/web.xml (you can put a dummy one) to indicate to the server this is a web archive if you want to use directory deployment.
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