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function is not described

_show_post_preview() WP 2.7.0

Filters the latest content for preview from the post autosave.

This is an internal function for using it by WP core itself. It's not recommended to use this function in your code.

No Hooks.

Return

null. Nothing.

Usage

_show_post_preview();

Code of _show_post_preview() WP 5.8.3

function _show_post_preview() {
	if ( isset( $_GET['preview_id'] ) && isset( $_GET['preview_nonce'] ) ) {
		$id = (int) $_GET['preview_id'];

		if ( false === wp_verify_nonce( $_GET['preview_nonce'], 'post_preview_' . $id ) ) {
			wp_die( __( 'Sorry, you are not allowed to preview drafts.' ), 403 );
		}

		add_filter( 'the_preview', '_set_preview' );
	}
}