I\'m, working on a Java servlet which runs on a Tomcat 8.0.18 server and uses the JSR356 websocket API to communicate with a browser. By default Tomcat uses the \"permessage
Please try to add jvm option
-Dorg.apache.tomcat.websocket.DISABLE_BUILTIN_EXTENSIONS=true
to catalina.bat (for windows) or catalina.sh (for unix like OS).
e.g. add this line at the beginning of catalina.sh
CATALINA_OPTS="-Dorg.apache.tomcat.websocket.DISABLE_BUILTIN_EXTENSIONS=true"
add this line at the beginning of catalina.bat
set CATALINA_OPTS="-Dorg.apache.tomcat.websocket.DISABLE_BUILTIN_EXTENSIONS=true"