If, when I’m looking through the comments, I spot an obvious typo, I will often fix it.
First, because as an editor it would drive me crazy not to.
Second, because as you know I’m a very careless typist (as many editors are), and it doesn’t seem fair that I can correct by own errors while other people can’t.
Comics I Don't Understand 
“by own errors”? ;)
Pwned! By & by
We get why this site hasn’t got a preview or edit function, so thanks.
That’s fuddy.
I just went back to see whether …involve gong back… had been corrected, but discovered that it wasn’t alone: “…involve gong back to 1865 and tying to prevent…” ;-)
You must be hallucinating, Kilby!
@CIDU Bill: Nice ty! ;)
Editing rule: there is always at least one mistake left.
You must have had a cold when you typed this.
I have never denied that, like many editors, I can spot other people’s typos with my eyes shut, while mine remain invisible to me.
You’re really better off being your own doctor, attorney or barber than being your own editor.