Problem with “Enable … for Logged-in Users?”

With WordPress 5.3 the option “Enable … for Logged-in Users?” displayed incorrectly for Minify, Combine and Page Caching.

I receive the following error messages at Minify and Combine:
WARNING [2] count(): Parameter must be an array or an object that implements Countable. Warning on line 811 in file ../wp-content/plugins/codedragon-smartcache/admin/class-sc-admin.php
WARNING [2] count(): Parameter must be an array or an object that implements Countable. Warning on line 817 in file ../wp-content/plugins/codedragon-smartcache/admin/class-sc-admin.php

And the following error messages are repetitive on Minify, Combine, and Page Caching on each role:
WARNING [2] Illegal string offset ‘administrator’. Warning on line 2558 in file ../wp-content/plugins/codedragon-smartcache/admin/class-sc-admin.php
WARNING [2] Cannot assign an empty string to a string offset. Warning on line 2558 in file ../wp-content/plugins/codedragon-smartcache/admin/class-sc-admin.php
WARNING [2] Illegal string offset ‘administrator’. Warning on line 2562 in file ../wp-content/plugins/codedragon-smartcache/admin/class-sc-admin.php

WARNING [2] Illegal string offset ‘editor’. Warning on line 2558 in file ../wp-content/plugins/codedragon-smartcache/admin/class-sc-admin.php
WARNING [2] Cannot assign an empty string to a string offset. Warning on line 2558 in file ../wp-content/plugins/codedragon-smartcache/admin/class-sc-admin.php
WARNING [2] Illegal string offset ‘editor’. Warning on line 2562 in file ../wp-content/plugins/codedragon-smartcache/admin/class-sc-admin.php
…

I really like the plugin and I did not install it before WP 5.3, so I do not know if the problem is related to the current (buggy) version of WordPress or if it is a problem with the plugin.

Can you please help?