If the parent's skeleton has a single node and belongs to the 'Isolated synaptic terminals' group, then reassign ownership of the skeleton and the neuron to the user. The treenode remains property of the original user who created it.
If the parent's skeleton has a single node and belongs to the
'Isolated synaptic terminals' group, then reassign ownership
of the skeleton and the neuron to the user. The treenode remains
property of the original user who created it.

This solve the issue with isolated synaptic terminals, which
have a skeleton and a neuron for consistency and simplicity only,
but these are only placeholders and only the treenode matters.

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