This is an open issue for anyone to leave links to conversations in open source communities that they think are particularly negative. As I'm designing the sentiment analysis to also recognize personal attacks, so I'm looking for threads that are: insulting, dismissive, rude, arrogant, insulting, unprofessional, condescending, inappropriate, hostile, accusatory, racist, sexist, homophobic, transphobic, classist, or ablist. Threads where a code of conduct was invoked or a person's behavior was corrected by core developers are a plus.
Reddit seems like a classic choice for negative examples. 🙃
This is a thread where a code of conduct was invoked and core developers corrected a person's behavior:
original post: https://mail.mozilla.org/pipermail/rust-dev/2011-May/000388.html
correction from core developer: https://mail.mozilla.org/pipermail/rust-dev/2011-May/000394.html
invocation of code of conduct: https://mail.mozilla.org/pipermail/rust-dev/2011-May/000390.html
This is a potentially interesting thread because it got contentious, but then de-escalated and went back to more productive discussion. (Though the original poster was later banned because of their conduct.)
There are lots of negative threads on the mozilla.governance mailing list: https://groups.google.com/forum/#!forum/mozilla.governance if you look at April 2014 and March and April 2012.
a discussion on introducing Code of Conduct at sagemath.org project that went totally out of hand. There was more than one thread on it around that date, so you might like to search for "code of conduct" on sagemath dev list.
The ongoing discussions over a Code of Conduct for GUADEC and by extension GNOME has some excellent examples of condescending and dismissive behaviour by at least one participant who is clearly attempting to derail the process.
I think the CoC PR discussion for Jupyter has both positive and negative examples.