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Changes between Initial Version and Version 1 of Ticket #10225, comment 6

initial	v1
1		Simple testing shows it works, but it could still be improved.
	1	Simple testing shows it works (on Windows), but it could still be improved.
2	2
3	3	First, using the chain of first children is not going to work in all cases, and using `changectx.descendants` as I first thought neither. Consider the following case, for the incoming sequence `b, c, d` where `d` is the merge of `b` and `c` (i.e. we have for example `a -> b, a -> c, (b, c) -> d`, with `a` being a changeset already present in the repository). If we start with `node == b`, we don't want to miss `c` even if it's not a descendant of `b`.