Ensure uniqueness when returning page lists in `get_page_children()`. Fixes failing unit tests.

Props boonebgorges.
Reverts [30246].
Fixes #14477.

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IETF language changes in MediaElement:
https://github.com/johndyer/mediaelement/pull/1270/

Reverts [28801].
Fixes #29182.

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When deleting media grid attachments, wait until the server responds before removing the model from its collection.

Props 5um17.
Fixes #30457.

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Fix edge-case in media cropping where selection and destination are the same size.

Adds unit tests.

Props mboynes.
Fixes #19793.

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Adjust the RegEx in `wp_check_filetype()` to be aware that query strings are thing that exist sometimes in URLs.

Adds unit tests.

Props voldemortensen.
Fixes #30377.

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Editor: no pointer for DFW v2 when editor-scrolling is not used. Pass `$post_type` in the `wp_editor_expand` filter. See #30458.
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