Could you please confirm that you use the 1.6 version. I put here a sample of XML definition (web.xml) as you mentionned it.
<!-- Embedded Console -->
<servlet>
<servlet-name>ff4j-console</servlet-name>
<servlet-class>org.ff4j.web.FF4jDispatcherServlet</servlet-class>
<init-param>
<param-name>ff4jProvider</param-name>
<param-value>org.ff4j.sample.SimpleFF4jProvider</param-value>
</init-param>
<load-on-startup>1</load-on-startup>
</servlet>
<servlet-mapping>
<servlet-name>ff4j-console</servlet-name>
<url-pattern>/ff4j-console/*</url-pattern>
</servlet-mapping>
Then please note that the URL MUST HAVE A SLASH at the end.
Your URL is not localhost:8443/bat/ff4j-console
but localhost:8443/bat/ff4j-console/
This should resolve the static not found and display all pictures.
This a issue of Thymeleaf and definition in XML (look you put /*). If you have ideas you're welcome it's defined here https://github.com/clun/ff4j/blob/master/ff4j-web/src/main/java/org/ff4j/web/FF4jServlet.java#L172-L182