[Bug] Plugin will Fatal Error without filesystem write access

Hello,
we wanted to use this plugin, however it looks like the plugin requires file write access (fwrite is in the code everywhere).

Example error:

PHP Warning: fopen([REMOVED]/wp-content/uploads/logs/mathcaptcha/sessions/.htaccess): Failed to open stream: Permission denied in [REMOVED]/wp-content/plugins/wp-advanced-math-captcha/includes/class-core.php on line 106

PHP Fatal error: Uncaught TypeError: fwrite(): Argument #1 ($stream) must be of type resource, bool given in [REMOVED]/wp-content/plugins/wp-advanced-math-captcha/includes/class-core.php:107

Best practices for WP calls for no/limited write access to file system for obvious security reasons. It would be great if the plugin can be refactored to either detect if there is write access, and/or remove write access to function.

Thanks.