Fixes mutual feeds defect when subscribers array is undefined.
Fixes mutual feeds defect when subscribers array is undefined.

dsumin/freefeed-html,SiTLar/pepyatka-html,epicmonkey/pepyatka-html,FreeFeed/freefeed-html,pepyatka/pepyatka-html,FreeFeed/freefeed-html,dsumin/freefeed-html,epicmonkey/pepyatka-html,pepyatka/pepyatka-html,SiTLar/pepyatka-html