  In this paper we answer two recent questions from Charlier et al. and Harju
about self-shuffling words. An infinite word $w$ is called self-shuffling, if
$w=\prod_{i=0}^\infty U_iV_i=\prod_{i=0}^\infty U_i=\prod_{i=0}^\infty V_i$ for
some finite words $U_i$, $V_i$. Harju recently asked whether square-free
self-shuffling words exist. We answer this question affirmatively. Besides
that, we build an infinite word such that no word in its shift orbit closure is
self-shuffling, answering positively a question from Charlier et al.
