Yeah you can find out, but that really shouldn’t matter (at least for the exception you are getting… we can take a look though.) There’s always a chance, because using the wrong version of prettyfaces/jsf tends to cause strange issues
Which app-server/version are you using?
Where are your JSF Jars?
If you open the JSF jars, take a look inside the META-INF/manifest.mf, it should tell you which version you have.
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