1 files changed, 14 insertions, 0 deletions

diff --git a/app/services/issues/update_service.rb b/app/services/issues/update_service.rb
index b54b0bf6ef6..fba252b0bae 100644
--- a/app/services/issues/update_service.rb
+++ b/app/services/issues/update_service.rb
@@ -48,6 +48,8 @@ module Issues
         notification_service.async.relabeled_issue(issue, added_labels, current_user)
       end
 
+      handle_milestone_change(issue)
+
       added_mentions = issue.mentioned_users - old_mentioned_users
 
       if added_mentions.present?
@@ -91,6 +93,18 @@ module Issues
 
     private
 
+    def handle_milestone_change(issue)
+      return if skip_milestone_email
+
+      return unless issue.previous_changes.include?('milestone_id')
+
+      if issue.milestone.nil?
+        notification_service.async.removed_milestone_issue(issue, current_user)
+      else
+        notification_service.async.changed_milestone_issue(issue, issue.milestone, current_user)
+      end
+    end
+
     # rubocop: disable CodeReuse/ActiveRecord
     def get_issue_if_allowed(id, board_group_id = nil)
       return unless id