An expanded sub-composition child row is built from a manifest clip, which
carries none of the host element's attributes, so data-hidden never reached
it. The eye on that row therefore always reported the element visible: the
first click hid it, and every click after wrote data-hidden again instead of
removing it. The element could not be shown again, not even after a reload,
because the attribute was already in the source.
The flat store element for the same child is built with its host element, so
the child row inherits hidden, timelineLocked and timelineRole from it.
Miguel Angel Simon Sierra
5dad52370f