MDN URL: https://developer.mozilla.org/en-US/docs/Web/HTTP/Headers/Content-Security-Policy/block-all-mixed-content

What information was incorrect, unhelpful, or incomplete?

block-all-mixed-content is marked as deprecated, however, there's no explication as to why it's deprecated and no suggestion of a replacement.

What did you expect to see?

I expected to either see a suggested replacement, or at least an explication of why block-all-mixed-content should not be used in the future.