Yes, this is expected it's a known caching quirk, not a leftover reference from the rewrite.

The sidebar "Contributors" widget is powered by a separate, cached statistics dataset that GitHub computes via a background indexing job it isn't a live query against your current commit history. This cache doesn't automatically invalidate the moment history changes; it only gets fully recomputed on its own schedule, which is why you can see it lag behind even after a clean force-push.

The fact that /graphs/contributors is already clean is a good sign — it confirms your git filter-repo rewrite fully succeeded in the underlying data. The sidebar widget just uses a more heavily cached path than the graphs page, so the two can be out of sync for a while after a history rewrite. Incognito won't help since this is server-side caching, not anything stored in your browser.

There's unfortunately no user-facing way to manually trigger a refresh. In practice:

• It typically clears on its own within 24–72 hours, sometimes longer on repos with more history.
• Pushing a new commit occasionally seems to nudge GitHub into recomputing stats sooner, though this isn't guaranteed or documented behavior.
• If it's still showing after a week or so, GitHub Support can manually force a contributor-stats recompute for your repo that's not something exposed to users otherwise.

Nothing you did was wrong this is just GitHub's stats cache lagging behind a history rewrite.

Yes, this can happen. GitHub’s contributor data is not necessarily updated at the same time as the repository’s commit history, so the sidebar widget can continue showing an old contributor even after a history rewrite.

Since /graphs/contributors is already clean and you’ve verified that the old identity no longer exists in either branch, I would just give GitHub some time to refresh the cached data. In my experience, it can take up to around 24 hours.

There doesn’t appear to be a manual refresh option for the sidebar contributor widget. I’d avoid doing additional force-pushes just to trigger it. If it’s still showing the old identity after 24 hours, contacting GitHub Support would probably be the next step.