diff --git a/guides/bug_report_templates/action_mailbox_gem.rb b/guides/bug_report_templates/action_mailbox_gem.rb
index 52dab0bfa1..5493a213d1 100644
--- a/guides/bug_report_templates/action_mailbox_gem.rb
+++ b/guides/bug_report_templates/action_mailbox_gem.rb
@@ -10,6 +10,11 @@ gemfile(true) do
   # Activate the gem you are reporting the issue against.
   gem "rails", "6.1.0"
   gem "sqlite3"
+  if RUBY_VERSION >= "3.1"
+    # net-smtp, net-imap and net-pop were removed from default gems in Ruby 3.1, but is used by the `mail` gem.
+    # So we need to add them as dependencies until `mail` is fixed: https://github.com/mikel/mail/pull/1439
+    gem "net-smtp", require: false
+  end
 end
 
 require "active_record/railtie"
diff --git a/guides/bug_report_templates/action_mailbox_main.rb b/guides/bug_report_templates/action_mailbox_main.rb
index 15d48c8320..7661940ff5 100644
--- a/guides/bug_report_templates/action_mailbox_main.rb
+++ b/guides/bug_report_templates/action_mailbox_main.rb
@@ -9,6 +9,11 @@ gemfile(true) do
 
   gem "rails", github: "rails/rails", branch: "main"
   gem "sqlite3"
+  if RUBY_VERSION >= "3.1"
+    # net-smtp, net-imap and net-pop were removed from default gems in Ruby 3.1, but is used by the `mail` gem.
+    # So we need to add them as dependencies until `mail` is fixed: https://github.com/mikel/mail/pull/1439
+    gem "net-smtp", require: false
+  end
 end
 
 require "active_record/railtie"