/usr/share/doc/libservlet3.1-java/api/element-list is in libservlet3.1-java-doc 8.5.30-1ubuntu1.
This file is owned by root:root, with mode 0o644.
The actual contents of the file can be viewed below.
1 2 3 4 5 6 7 8 9 10 | javax.el
javax.servlet
javax.servlet.annotation
javax.servlet.descriptor
javax.servlet.http
javax.servlet.jsp
javax.servlet.jsp.el
javax.servlet.jsp.tagext
javax.websocket
javax.websocket.server
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