Revert [27115] and let cache backends handle the stripping of spaces in cache keys as necessary.

microtime() returns greater precision than microtime(true).

see #27000, #23448, #26903, #14485.

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Improve inline documentation for `WP_Users_List_Table`.

Props leewillis77 for the initial patch.
Fixes #26564.

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Introduce HTML5 gallery support.

When a theme supports HTML5 galleries via add_theme_support( 'html5', 'gallery' ), figure and figcaption will be used instead of definition list markup.

props obenland.
fixes #26697.

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Move comment-reply.js to the footer.

While it can function before the page is loaded, it works by moving the comment form, which is usually toward the bottom of the page. Please report any contraindications on the ticket.

props obenland.
fixes #12641.

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Add a $default argument to get_query_var() and WP_Query::get().	fixes #16471.

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Unslash in the time-format and date-format ajax endpoints.

props GregLone.
fixes #27216.

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Themes screen: Clicking back through history should properly close the overlay.

props gcorne.
fixes #27198.

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