@7725718e I read it the same way as you. Only Firefox is following the spec. So good of the spec authors to address what is likely a common error.
@1e8ded32 Agreed, Firefox is the only one who is trimming the string. The ironic thing regarding the web page I was testing is that aria-label isn't needed at all on these links because the images all had appropriate alt text for the links. Thanks for taking my quiz.