Custom Post Type UI non compatible with php 8

Hi thanks for your reply.
This is the error message just only when I active php8 :

Fatal error: Uncaught TypeError: in_array(): Argument #2 ($haystack) must be of type array, bool given in /home/primed/ccc/wp-content/themes/cmca/loop-film.php:18 Stack trace: #0 /home/primed/ccc/wp-content/themes/cmca/loop-film.php(18): in_array(false, false) #1 /home/primed/ccc/wp-includes/template.php(772): require('/home/primed/cc...') #2 /home/primed/ccc/wp-includes/template.php(716): load_template('/home/primed/cc...', false, Array) #3 /home/primed/ccc/wp-includes/general-template.php(204): locate_template(Array, true, false, Array) #4 /home/primed/ccc/wp-content/themes/cmca/single-film.php(33): get_template_part('loop', 'film') #5 /home/primed/ccc/wp-includes/template-loader.php(106): include('/home/primed/cc...') #6 /home/primed/ccc/wp-blog-header.php(19): require_once('/home/primed/cc...') #7 /home/primed/ccc/index.php(17): require('/home/primed/cc...') #8 {main} thrown in /home/primed/ccc/wp-content/themes/cmca/loop-film.php on line 18

I hope that you can help me.

ok this is loop-film.php :

<?php 
	global $graphene_settings; 
	$post_type = get_post_type_object( get_post_type() );
?>
<?php 
/**
 * Check if the post has a post format. Load a post-format specific loop file,
 * if it has. Continue with standard loop otherwise.
*/ 
if ( function_exists( 'get_post_format' ) ) {
	global $post_format;
	$post_format = get_post_format();
	
	// Get the post formats supported by the theme
	$supported_formats = get_theme_support( 'post-formats' );
	if ( is_array( $supported_formats ) ) $supported_formats = $supported_formats[0]; 
	
	if ( in_array( $post_format, $supported_formats ) ) {
		
		// Get the post format loop file
		get_template_part( 'loop-post-formats', $post_format );
		
		// Stop this default posts loop
		return;
	}
}
?>

<?php /* Post navigation */ ?>
<?php graphene_post_nav(); ?>
        
<div id="post-<?php the_ID(); ?>" <?php post_class( 'clearfix post' ); ?>>
	
	<?php do_action( 'graphene_before_post' ); ?>
	
	<div class="entry clearfix">
    	
        <?php /* Post date */ ?>
        <?php if ( stristr( graphene_post_date_setting( get_the_ID() ), 'icon' ) ) graphene_post_date(); ?>
		
        <?php /* Show the post author's gravatar if enabled */
		if ( $graphene_settings['show_post_avatar'] ) {
			echo '<div class="post-avatar-wrap gutter-left">' . get_avatar( get_the_author_meta( 'user_email' ), 45 ) . '</div>';
		} 
		?>
        
        <?php 
		/* Add a print button only for single pages/posts 
		 * and if the theme option is enabled.
		 */
		if ( $graphene_settings['print_button'] ) : ?>
			<?php graphene_print_button( $post_type ); ?>
		<?php endif; ?>
        
        <?php /* Add an email post icon if the WP-Email plugin is installed and activated */
			if( function_exists( 'wp_email' ) ) { echo '<p class="email wp-email-button">'; email_link(); echo '</p>'; }
		?>
        
		<?php /* Post title */ ?>
        <h1 class="post-title-film">
			<?php if ( get_the_title() == '' ) { _e( '(No title)', 'graphene' ); } else { the_title(); } ?>
			<?php do_action( 'graphene_post_title' ); ?>
        </h1>
		
		<?php /* Post meta */ ?>
		<div class="post-supercat">		<strong>ANN&EgraveE DE PARTICIPATION AU PriMed : </strong>
		<?php                  the_terms( $post->ID, 'a-participation' ,  '' );                    ?>		<br/>		<strong>CATEGORIE D'INSCRIPTION : </strong>		<?php                  the_terms( $post->ID, 'cat_inscription' ,  '' );                    ?>			</div>		
			<?php /* Edit post link, if user is logged in */ ?>		<div class="post-meta clearfix">
			<?php if ( is_user_logged_in() ) : ?>
			<p class="edit-post">
				<?php edit_post_link( sprintf( __( 'Edit %s', 'graphene' ), $post_type->labels->singular_name ), ' (', ')' ); ?>
			</p>
			<?php endif; ?>
            
            <?php /* Microdata field for "Updated" */ ?>
            <?php if ( ! graphene_should_show_date() ) : ?>
            <span class="updated"><span class="value-title" title="<?php the_time( 'Y-m-d\TH:i' ); ?>" /></span>
            <?php endif; ?>
			
			<?php /* Inline post date */ ?>
			<?php if ( graphene_post_date_setting( get_the_ID() ) == 'text' ) graphene_post_date(); ?>
			
			<?php /* Post author, not shown if admin decides to hide it */ ?>
			<?php if ( $graphene_settings['hide_post_author'] != true ) : ?>
			<p class="post-author author vcard">
				<?php
				/* translators: this is for the author byline, such as 'by John Doe' */
				$author_url = '<a href="' . get_author_posts_url( get_the_author_meta( 'ID' ) ) . '" class="url">' . get_the_author_meta( 'display_name' ) . '</a>';
				printf( __( 'by %s', 'graphene' ), '<span class="fn nickname">' . apply_filters( 'graphene_author_url', $author_url ) . '</span>' );
				?>
			</p>
			<?php endif; ?>
								
			<?php /* For printing: the date of the post */
			if ( $graphene_settings['print_css'] && graphene_should_show_date() ) {
				 echo graphene_print_only_text( '<em>' . get_the_time( get_option( 'date_format' ) ) . '</em>' );  
			}
			?>
			
			<?php do_action( 'graphene_post_meta' ); ?>
		</div>
		
		<?php /* Post content */ ?>
		<div class="entry-content clearfix">
			<?php do_action( 'graphene_before_post_content' ); ?>
				
			<?php /* Social sharing buttons at top of post */ ?>
			<?php if ( stripos( $graphene_settings['addthis_location'], 'top' ) !== false ) { graphene_addthis( get_the_ID() ); } ?>
				
			<?php /* The full content */ ?>
			<?php the_content(); ?>
			
			<?php wp_link_pages( array( 'before' => '<div class="link-pages"><p><strong>' . __( 'Pages:','graphene' ) . '</strong> ', 'after' => '</p></div>', 'next_or_number' => 'number' ) ); ?>
			
			<?php do_action( 'graphene_after_post_content' ); ?>
			
		</div>
		
		<?php /* Post footer */ ?>
		<div class="entry-footer clearfix">
			<?php /* Display the post's tags, if there is any */ ?>
			<?php if ( $graphene_settings['hide_post_tags'] != true ) : ?>
				<p class="post-tags"><?php if ( has_tag() ) { _e( 'Tags:','graphene' ); the_tags( ' ', ', ', '' ); } else { _e( 'This post has no tag','graphene' ); } ?></p>
			<?php endif; ?>
			
			<?php 
			/* Display AddThis social sharing button */
			if ( stripos( $graphene_settings['addthis_location'], 'bottom' ) !== false) { graphene_addthis( get_the_ID() ); } 
			?>
			
			<?php do_action( 'graphene_post_footer' ); ?>
		</div>
	</div>
</div>

<?php 
/**
 * Display the post author's bio in single-post page if enabled
*/
if ( $graphene_settings['show_post_author'] ) :
?>
<h4 class="author_h4 vcard"><?php _e( 'About the author', 'graphene' ); ?></h4>
<div class="author-info clearfix">
	<div <?php graphene_grid( 'author-avatar-wrap', 2, 2, 2, true ); ?>>
	<?php
	if ( $author_imgurl = get_the_author_meta( 'graphene_author_imgurl' ) ) {
		echo '<img class="avatar" src="' . $author_imgurl . '" alt="" />';
	} else {
		echo get_avatar( get_the_author_meta( 'user_email' ), graphene_grid_width( '', 2 ) ); 
	}
	?>
    </div>
	<p class="author_name"><strong><?php the_author_meta( 'display_name' ); ?></strong></p>
	<div class="author_bio"><?php echo wpautop( get_the_author_meta( 'description' ) ); ?></div>
	
</div>
<?php endif; ?>

<?php /* For printing: the permalink */
	if ( $graphene_settings['print_css'] ) {
		echo graphene_print_only_text( '<span class="printonly url"><strong>' . __( 'Permanent link to this article:', 'graphene' ) . ' </strong><span>' . get_permalink() . '</span></span>' );
	}
?>

<?php 
/**
 * Display Adsense advertising for single post pages 
 * See graphene_adsense() function in functions.php
*/ 
graphene_adsense(); ?>

<?php /* Get the comments template for single post pages */ ?>
<?php comments_template(); ?>

<?php do_action( 'graphene_loop_footer' ); ?>

This is line 18 :

if ( in_array( $post_format, $supported_formats ) ) {

Thanks for your reply.
It works.
Thanks a lot for your help.