With tomcat 6.0.26 on windows, starting the examples app, browse a page and press crtl-C in the tomcat window causes tomcat to complain about a possible memory leak:
SEVERE: A web application created a ThreadLocal with key of type [java.lang.ThreadLocal] (value [java.lang.ThreadLocal@bf015]) and a value of type [org.apache.click.Context.ContextStack] (value []) but failed to remove it when the web application was stopped. To prevent a memory leak, the ThreadLocal has been forcibly removed.
It is caused by Context.hasThreadLocalContext() which creates an empty ContextStack if none existed before. Which is called by PerformanceFilter's attempt to find the application version number.