If you expand subscribers on your settings page, you will now see
a query like this in your postgres logs:
SELECT "zerver_userprofile"."email"
FROM "zerver_subscription" INNER JOIN "zerver_recipient" ON ("zerver_subscription"."recipient_id" = "zerver_recipient"."id") INNER JOIN "zerver_userprofile" ON ("zerver_subscription"."user_profile_id" = "zerver_userprofile"."id") WHERE ("zerver_recipient"."type" = 2 AND "zerver_subscription"."active" = true AND "zerver_recipient"."type_id" = 40 AND "zerver_userprofile"."is_active" = true )
The join's still complicated, but the list of fields is one instead of 40+.
(imported from commit 48de1f888193a4d23fcea52d0b633d134e4a3ff7)
d24d8e4b36