Warning: Undefined array key “hide_for_logged_in”

Hello, I hope you can help me.
I installed a new template and now only have one login widget (unfortunately, the standard one from https://bbq.gdz.bplaced.net is missing) and the one from you. I get an error message:
“Warning: Undefined array key ‘hide_for_logged_in’ in /users/gdz/www/wp-content/plugins/super-socializer/inc/widget.php on line 24”
The file contains the following in line 24:
if($instance[‘hide_for_logged_in’]==1 && is_user_logged_in()) return;

How can I get the widget to display correctly without an error message?

Thanks for Help

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