Delete this text and add "fixes #(issue number)".

Do not just list issue numbers here as they will not be automatically closed on merging this pull request unless prefixed with "fixes" or "closes".

Delete this text and answer yes/no and explain.

If yes, this pull request will need to wait for the next major release (0.{x + 1}.0)

Behavior changes can be breaking if significant enough. Consider Hyrum's Law:

With a sufficient number of users of an API,
it does not matter what you promise in the contract:
all observable behaviors of your system
will be depended on by somebody.