Site crash

Hello and thank you for the plugin. It worked very well until last week. Every time I was saving a post, publishing or something else my site was crashing.
These are the logs, after I deactivated the plugin everything works well.

[14-Sep-2022 10:57:46 UTC] PHP Fatal error:  Uncaught TypeError: sizeof(): Argument #1 ($value) must be of type Countable|array, bool given in /var/www/wordpress/wp>
Stack trace:
#0 /var/www/wordpress/wp-content/plugins/autopost-to-mastodon/mastodon_autopost.php(324): autopostToMastodon->getTootFromTemplate()
#1 /var/www/wordpress/wp-includes/class-wp-hook.php(309): autopostToMastodon->toot_post()
#2 /var/www/wordpress/wp-includes/class-wp-hook.php(331): WP_Hook->apply_filters()
#3 /var/www/wordpress/wp-includes/plugin.php(476): WP_Hook->do_action()
#4 /var/www/wordpress/wp-includes/post.php(4673): do_action()
#5 /var/www/wordpress/wp-includes/revision.php(334): wp_insert_post()
#6 /var/www/wordpress/wp-includes/revision.php(190): _wp_put_post_revision()
#7 /var/www/wordpress/wp-includes/class-wp-hook.php(309): wp_save_post_revision()
#8 /var/www/wordpress/wp-includes/class-wp-hook.php(331): WP_Hook->apply_filters()
#9 /var/www/wordpress/wp-includes/plugin.php(476): WP_Hook->do_action()
#10 /var/www/wordpress/wp-includes/post.php(4642): do_action()
#11 /var/www/wordpress/wp-includes/post.php(4775): wp_insert_post()
#12 /var/www/wordpress/wp-admin/includes/post.php(426): wp_update_post()
#13 /var/www/wordpress/wp-admin/post.php(227): edit_post()
#14 {main}

Thank you