Confusing filter sets check message

[pun-ky]

    <MAJOR> / - Listener error: javax.jcr.ItemNotFoundException "Root has no parent" [aem-groovy-console-13.0.0.zip]
  net.adamcin.oakpal.core/basic/filterSets

what does it mean? is it a bug/ unexpected?

[pun-ky]

also reported in Groovy Console as of it contains sth strange causing not passing validation icfnext/aem-groovy-console#97