I’ve chatted with aMemember and they said the following:
I believe it is issue with "SG Optimizer" plugin.
They do action wp without argument WP:
do_action( 'wp' );
/public_html/wp-content/plugins/sg-cachepress/core/Front_End_Optimization/Front_End_Optimization.php(315)
but argument (WP instance) is required according WP documentation:
https://developer.ww.wp.xz.cn/reference/hooks/wp/
aMember rely on this action and on its proper call.
So, I assume this is some kind of bug in the plugin?
Thanks.