Hi.
I have the same notices, as Djib’s in admin pages when I trying to enable filter by is_feed() from advanced_options page
With disabled filter by page types I have no error displaying in admin page, but in blog and in /feed/ pages I can see next notices in debug mode
Notice: Undefined index: HTTPS in /wp-content/plugins/wp-super-cache/wp-cache-phase1.php on line 526
Notice: Undefined index: HTTP_X_FORWARDED_PROTO in /wp-content/plugins/wp-super-cache/wp-cache-phase1.php on line 526
Warning: Cannot modify header information – headers already sent by (output started at /wp-content/plugins/wp-super-cache/wp-cache-phase1.php:526) in /wp-content/plugins/wp-super-cache/wp-cache-phase2.php on line 76
