Wildfly 14 mixes up HTML response in JSF applications

Introduced in wildfly 14 we receive a new JSF implementation (developed years ago), which is based on mojarra 2.3.5. In certain circumstances this JSF runtime hides the real problem, and makes from an invalid HTML a valid one, and spoils it somewhere else you would never guess, or produces an invalid partial response. Anything can happen, and the real problem will be really hard to find. This behavior led to a more severe error than the original one in two reported cases at github.

I opened an issue (eclipse-ee4j/mojarra#4488) about this, but the mojarra development team closed this issue without solving it. Now a lot of teams starting to move towards wildfly 14. They are likely to face similar magical errors like us. In the other case (jboss/mojarra#21) the developer team switched back to JSF 2.2. I’m also worried to change to wildfly 14, because of the future magical errors it will cause in our systems.