Wish I knew there was a thread about this otherwise I wouldn’t have embarassed myself! Twice with the OP!!!
Havre by Juliet Berto (the Julie in Celine and Julie Go Boating) has a subplot about a child playing through a PC game that mirrors the plot of the film as it happens. It only exists on VHS and there’s one print of it in existence that’s not likely to be restored due to rights issues but its as good as anything Rivette directed with her.
(fin)