Correct ! LiterateMultiBranchProject derives from MultiBranchProject which is indeed a derivation of AbstractItem. It provides getTriggers outside of all interface / derivation, under assumptions given by the genericity. Therefore, I don't see how to support MultiBranchProject in this extension : should I go forward with the ParameterizedJobMixIn rewrite, hope that MultiBranchProject implements ParameterizedJobMixIn.ParameterizedJob and require Jenkins 1.558 ? I don't feel comfortable requiring the absolute latest version of Jenkins just for my extension, but if you wish, we can !