Evil php error

Fatal error: Uncaught Error: array_key_exists(): Argument #2 ($array) must be of type array, bool given
in /home/xyz.com/public_html/wp-content/plugins/11sight-video-audio-calls-and-text-chat/core.php on line 347

Call stack:

iisight_options_page_html()
wp-includes/class-wp-hook.php:292
WP_Hook::apply_filters()
wp-includes/class-wp-hook.php:316
WP_Hook::do_action()
wp-includes/plugin.php:484
do_action()
wp-admin/admin.php:259

Their own chat:
We’re sorry, but something went wrong.
If you are the application owner check the logs for more information.

Tried to email them:
No confirmation that it was sent. The form just disappeared.

Disheartening that there’s an open issue open for over a year that might be the same.