Commit message wrapped differently when amending git commit

In QtCreator, when amending a git commit with multi-line commit message, you can often see that the old commit message is wrapped differently from how it was originally typed (also in QtCreator). Some of the words that were originally at the end of the line are wrapped to the next line in the editor. The wrapped words tend to be the only ones on the line, since the newline after the word is also preserved. I can move them back to the end of the previous line, but on the next amend the message text will be incorrectly wrapped again.