Tested on Firefox 22 (Monobook) and Chrome 28 (Vector)
Steps to reproduce:
- Open any random page in the visual editor. Personally i used [[Botnet]].
- Add the word "Test" to the page.
- Press Ctrl + Z to undo the edit. Keep pressing till the edit is gone, then press it once more.
Once you have done this, the Redo button and the Redo shortcut (Ctrl+Shift+Z) no longer seem to restore the previous edits. Any subsequent edit seems to reset the undo / redo buttons to an "There were no previous edits" state.
Besides the above result that i can always reproduce using these steps, i have seen various other results. I have seen each of these at least twice but no matter what i try, i cannot seem to find any method of reproducing these reliably.
- An entry in the console log stating "Error: Cannot roll back a transaction that has not been committed "
- An entry in the console log stating "Error: Range error: Range is no longer valid after DOM mutation ([WrappedRange("Zz":1, "Zz":1)]) "
- The redo button suddenly inserting "♙" once in Chrome.
- The undo button suddenly inserting an endless steam "♙" in Firefox.