It isn't a bug as such as the change name function doesn't include updating existing content such as quoted posts, likes, etc.
Mike has said he will look into it when he gets the time though.
Actually, this is a particular place that effectively can't be changed because of how the data is cached. (Well, it can be changed, but it's probably a lot more work than it's worth.)
I was going by this post, specifically the part in bold:
Actually, this is a particular place that effectively can't be changed because of how the data is cached. (Well, it can be changed, but it's probably a lot more work than it's worth.)
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And P.S. - I didn't realize this was a bug report, sorry! Never mind, then!