The wait loop uses XPeekEvent(dpy, &e),
which can block indefinite if queue is empty.
Replace with timeout only _and_ only wait on CreateWindow0(..)
not when queried via X11Display dispatch loop on events
when it is assumed the information has been propagated already.
commit 578edfc20915e2e2aa18aa06e49f7341f86990c4 fixes this issue as described.