TL;DR: In what circumstances is it ok (by CGCC and politeness standards) to edit directly a post (be it challenge, answer, sandbox question, etc), assuming the edit is done in good faith?
I know people can rollback edits and further edit a post, but in the meantime that goes from the unwanted edit and the correction, many things can happen. What is more, the OP doesn't get notified when the post is edited, so it could take a long time before the OP realizes the post was badly edited.
I was under both ends of the "edit without consulting the OP" situation (bullet points below) and wanted to clarify it for me and for other users
[I edited without consulting OP] Recently I wrote a challenge and, later on, I added a couple of test cases. A particular user had a Python answer (a language I know how to write in) and so I took the user's TIO link, added the test cases and edited the answer to include the new link. I thought I was not doing any harm.
Of course I managed to edit at the same time as the user and so, they edited to golf the question and I submitted my edit which overwrote the user's golf. The user talked to me and asked I leave a TIO link next time, without directly editing the question. In hindsight I think the user was completely right and it would've been even easier for me to just drop the TIO link in the comments.
[my posts were edited without my consent] I wrote a couple of sandboxed challenges and I didn't include any test cases, as I wanted a bit of preliminary feedback first; a user edited both my challenges and for each, did a combination of
- create reference programs and include TIO links as if they were mine;
- create a test case section with text written in the first person, so effectively impersonating me;
- addressing some of the feedback left in the comments (which was fair feedback) but that was more than a trivial change;
I am not sure I have the "authority" to make this statement, but I'd suggest people mention one situation per answer and the community votes to agree/disagree with the answer.
The answer should clearly state if the situation mentioned is a "not ok to edit" situation or a "it is ok to edit" situation, along with a short description, in the header.
Rules here take effect if they have at least five upvotes and have at least twice as many upvotes as downvotes.
Related but 6 years old already and only one answer.