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This attempts to correct #21126 , where the content of the page is not
center-aligned.
(Note: I think this contains the right commits - but, those other
commits seem superfluous. I'm not sure I've made the pull request
correctly. I don't often use the pull request pattern when working,
opting to use the merge-request pattern instead for my workplace. If
there are any issues, please let me know and I will try to correct
them.)
Co-authored-by: wxiaoguang <wxiaoguang@gmail.com>