[D1X] Pull out follow-backs for higher signal (#4719)

* Pull out follow-backs for higher signal

* Gate it

* Fix early gate check

---------

Co-authored-by: Dan Abramov <dan.abramov@gmail.com>

src/state/queries/notifications/unread.tsx

@@ -8,6 +8,7 @@ import {useQueryClient} from '@tanstack/react-query'
 import EventEmitter from 'eventemitter3'
 
 import BroadcastChannel from '#/lib/broadcast'
+import {useGate} from '#/lib/statsig/statsig'
 import {logger} from '#/logger'
 import {useAgent, useSession} from '#/state/session'
 import {resetBadgeCount} from 'lib/notifications/notifications'
@@ -47,6 +48,7 @@ export function Provider({children}: React.PropsWithChildren<{}>) {
   const agent = useAgent()
   const queryClient = useQueryClient()
   const moderationOpts = useModerationOpts()
+  const gate = useGate()
 
   const [numUnread, setNumUnread] = React.useState('')
 
@@ -149,6 +151,7 @@ export function Provider({children}: React.PropsWithChildren<{}>) {
             // only fetch subjects when the page is going to be used
             // in the notifications query, otherwise skip it
             fetchAdditionalData: !!invalidate,
+            shouldUngroupFollowBacks: () => gate('ungroup_follow_backs'),
           })
           const unreadCount = countUnread(page)
           const unreadCountStr =
@@ -189,7 +192,7 @@ export function Provider({children}: React.PropsWithChildren<{}>) {
         }
       },
     }
-  }, [setNumUnread, queryClient, moderationOpts, agent])
+  }, [setNumUnread, queryClient, moderationOpts, agent, gate])
   checkUnreadRef.current = api.checkUnread
 
   return (