Allow @username@domain/@username in follow form, prevent duplicate accounts

created via remote look-up when domains differ but point to the same resource

app/controllers/api/v1/follows_controller.rb

@@ -5,7 +5,13 @@ class Api::V1::FollowsController < ApiController
   def create
     raise ActiveRecord::RecordNotFound if params[:uri].blank?
 
-    @account = FollowService.new.call(current_user.account, params[:uri].strip).try(:target_account)
+    @account = FollowService.new.call(current_user.account, target_uri).try(:target_account)
     render action: :show
   end
+
+  private
+
+  def target_uri
+    params[:uri].strip.gsub(/\A@/, '')
+  end
 end