Problems with the Digits plugin

Hi.

It seems that the new version of fastest cache plugin has a conflict with the Digits plugin.
If the plugin cache is not cleared after one day, an error is displayed during login / registration using the Digits plugin. To fix this error, it is necessary to clear the plugin cache once.
The error created in the server log is displayed below:

#0 /home/parsmora/domains/parsmorakabat.com/public_html/wp-includes/formatting.php(4553): wp_check_invalid_utf8(Object(WP_Error))
#1 /home/parsmora/domains/parsmorakabat.com/public_html/wp-content/plugins/wp-fastest-cache/inc/preload.php(490): esc_html(Object(WP_Error))
#2 /home/parsmora/domains/parsmorakabat.com/public_html/wp-content/plugins/wp-fastest-cache/wpFastestCache.php(1620): PreloadWPFC::create_preload_cache(Object(stdClass))
#3 /home/parsmora/domains/parsmorakabat.com/public_html/wp-includes/class-wp-hook.php(307): WpFastestCache->create_preload_cache()
#4 /home/parsmora/domains/parsmorakabat.com/public_html/wp-includes/class-wp-hook.php(331): WP_Hook->apply_filters(”, Array)
#5 /home/parsmora/domains/parsmorakabat.com/public_html/wp-includes/plugin.php(524): WP_Hook->do_action(Array)
#6 /home/parsmora/domains/parsmorakabat. in /home/parsmora/domains/parsmorakabat.com/public_html/wp-includes/formatting.php on line 1098

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