You might not want to hear this but no one does this. Should they? probably. But most people don't use Ctrl+C, Ctrl+V in the first place for SO answers.
Just a single data point, but when I copy & paste a snippet from Stack Overflow, I always add a comment "// source: https://stack overflow.com/questions/xxx#yyy".
I both find it respectful of who wrote the answer in the first place and useful for future users of the code: the Stack Overflow answer often provides context and explanation for what would otherwise be an obscure piece of code.
Pretty darn useful if you ask me: those who want to have more information can follow the link, casual readers can skip it, and the whole process if fair to the author.
