Today I found a rather weird case where a question had been vandalized by another user to a completely different question.
I did a search here and saw a lot of posts on vandalizing questions posted by oneself but this appears to be a different problem.
The original question was posted long back 6 years ago and the post was vandalized 2 years ago. In this case the original asker does get some notification about the revision but somehow this was not acted upon by the asker.
I have reverted it back to the original so that the answers are in sync with the question.
Is this a frequent problem here? What is the right approach to discourage these users who vandalize posts by others?
One can check that the edit was approved by two users (one of them is a highly active reviewer) and rejected by another user. This is also rather strange. Maybe the suggested edits need to be reviewed with more focus.