This will be fixed in the next build.
There are a few scenarios where rollback will fail. One is rolling back to the current revision. Another is rolling back to a revision that exactly matches the current revision.
As such, when we first introduced rollbacks in 2008, we hid the rollback button if:
- We were looking at the current revisions
- OR The current revision was "Rollback to Revision
N" and we were looking at Revision
Less than a year later when we refactored the view, we converted that OR to an AND, meaning we showed the button on every revision except the current one, but also on the current one if it was a rollback.
This probably went under the radar for a decade because we were actually suppressing the error message. This is because, as I recently discovered, zero-change edits execute rollbacks and we didn't want to show errors when they hit these conditions.
The reason the errors are visible now, and probably why this came to your attention, is that I fixed a bug that was hiding "Rollback" in the post menu and made changes to resurface the error message when I was confronted with a button that just wouldn't go away no matter how many times I clicked.