This resonates hard. I'm a heavy branching user too and kept losing track of context across sessions and threads.

That's actually why I built UltraContext (Show HN is live today). It's infrastructure for this exact problem: persistent context with version history, so you can fork, rewind, and track how conversations evolve over time.

Not a ChatGPT plugin (yet), but the API could power something like what you're describing. Would love to chat if you're interested in exploring this.