When flame wars break out, you can lock conversations on issues, pull requests, and commits until cooler heads prevail.
While a conversation is locked, only people with collaborator permissions can add comments.
In the right margin of the issue or pull request, click Lock issue or Lock pull request.
Read the information about locking conversations and click Lock this issue or Lock this pull request.
When you're ready to unlock the conversation, click Unlock issue or Unlock pull request.