javax.servlet.ServletException: java.lang.Error: This page expects a form submission
org.kohsuke.stapler.Stapler.invoke(Stapler.java:569)
org.kohsuke.stapler.MetaClass$13.dispatch(MetaClass.java:359)
org.kohsuke.stapler.Stapler.invoke(Stapler.java:534)
org.kohsuke.stapler.MetaClass$5.doDispatch(MetaClass.java:181)
org.kohsuke.stapler.NameBasedDispatcher.dispatch(NameBasedDispatcher.java:30)
org.kohsuke.stapler.Stapler.invoke(Stapler.java:534)
org.kohsuke.stapler.Stapler.invoke(Stapler.java:450)
org.kohsuke.stapler.Stapler.service(Stapler.java:132)
javax.servlet.http.HttpServlet.service(HttpServlet.java:717)
hudson.util.PluginServletFilter$1.doFilter(PluginServletFilter.java:94)
hudson.plugins.greenballs.GreenBallFilter.doFilter(GreenBallFilter.java:51)
hudson.util.PluginServletFilter$1.doFilter(PluginServletFilter.java:97)
hudson.util.PluginServletFilter.doFilter(PluginServletFilter.java:86)
hudson.security.csrf.CrumbFilter.doFilter(CrumbFilter.java:47)
hudson.security.ChainedServletFilter$1.doFilter(ChainedServletFilter.java:84)
hudson.security.ChainedServletFilter.doFilter(ChainedServletFilter.java:76)
hudson.security.HudsonFilter.doFilter(HudsonFilter.java:164)
java.lang.Error: This page expects a form submission
org.kohsuke.stapler.RequestImpl.getSubmittedForm(RequestImpl.java:726)
hudson.model.Computer.doConfigSubmit(Computer.java:971)
sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:48)
sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:25)
java.lang.reflect.Method.invoke(Method.java:600)
org.kohsuke.stapler.Function$InstanceFunction.invoke(Function.java:259)
org.kohsuke.stapler.Function.bindAndInvoke(Function.java:126)
org.kohsuke.stapler.Function.bindAndInvokeAndServeResponse(Function.java:65)
org.kohsuke.stapler.MetaClass$1.doDispatch(MetaClass.java:79)
org.kohsuke.stapler.NameBasedDispatcher.dispatch(NameBasedDispatcher.java:30)
org.kohsuke.stapler.Stapler.invoke(Stapler.java:534)
org.kohsuke.stapler.MetaClass$13.dispatch(MetaClass.java:359)
org.kohsuke.stapler.Stapler.invoke(Stapler.java:534)
org.kohsuke.stapler.MetaClass$5.doDispatch(MetaClass.java:181)
org.kohsuke.stapler.NameBasedDispatcher.dispatch(NameBasedDispatcher.java:30)
org.kohsuke.stapler.Stapler.invoke(Stapler.java:534)
org.kohsuke.stapler.Stapler.invoke(Stapler.java:450)
org.kohsuke.stapler.Stapler.service(Stapler.java:132)
javax.servlet.http.HttpServlet.service(HttpServlet.java:717)
hudson.util.PluginServletFilter$1.doFilter(PluginServletFilter.java:94)
hudson.plugins.greenballs.GreenBallFilter.doFilter(GreenBallFilter.java:51)
hudson.util.PluginServletFilter$1.doFilter(PluginServletFilter.java:97)
hudson.util.PluginServletFilter.doFilter(PluginServletFilter.java:86)
hudson.security.csrf.CrumbFilter.doFilter(CrumbFilter.java:47)
hudson.security.ChainedServletFilter$1.doFilter(ChainedServletFilter.java:84)
hudson.security.ChainedServletFilter.doFilter(ChainedServletFilter.java:76)
hudson.security.HudsonFilter.doFilter(HudsonFilter.java:164)
I do get the same exception while I try to save the hudson config (not slave).