diff --git a/activerecord/lib/active_record/test_fixtures.rb b/activerecord/lib/active_record/test_fixtures.rb
index 2b512a38a74dd..dafb7aca3c8a1 100644
--- a/activerecord/lib/active_record/test_fixtures.rb
+++ b/activerecord/lib/active_record/test_fixtures.rb
@@ -189,19 +189,22 @@ def enlist_fixture_connections
       # need to share a connection pool so that the reading connection
       # can see data in the open transaction on the writing connection.
       def setup_shared_connection_pool
+        return if ENV["OFFFFFFF"]
         if ActiveRecord::Base.legacy_connection_handling
-          writing_handler = ActiveRecord::Base.connection_handlers[ActiveRecord::Base.writing_role]
+          ActiveSupport::Deprecation.silence do
+            writing_handler = ActiveRecord::Base.connection_handlers[ActiveRecord::Base.writing_role]
 
-          ActiveRecord::Base.connection_handlers.values.each do |handler|
-            if handler != writing_handler
-              handler.connection_pool_names.each do |name|
-                writing_pool_manager = writing_handler.send(:owner_to_pool_manager)[name]
-                return unless writing_pool_manager
+            ActiveRecord::Base.connection_handlers.values.each do |handler|
+              if handler != writing_handler
+                handler.connection_pool_names.each do |name|
+                  writing_pool_manager = writing_handler.send(:owner_to_pool_manager)[name]
+                  return unless writing_pool_manager
 
-                writing_pool_config = writing_pool_manager.get_pool_config(nil, :default)
+                  writing_pool_config = writing_pool_manager.get_pool_config(nil, :default)
 
-                pool_manager = handler.send(:owner_to_pool_manager)[name]
-                pool_manager.set_pool_config(nil, :default, writing_pool_config)
+                  pool_manager = handler.send(:owner_to_pool_manager)[name]
+                  pool_manager.set_pool_config(nil, :default, writing_pool_config)
+                end
               end
             end
           end
diff --git a/activerecord/test/cases/base_prevent_writes_test.rb b/activerecord/test/cases/base_prevent_writes_test.rb
index e0e8489cececc..2773f65b69f72 100644
--- a/activerecord/test/cases/base_prevent_writes_test.rb
+++ b/activerecord/test/cases/base_prevent_writes_test.rb
@@ -202,7 +202,6 @@ def teardown
       end
 
       test "preventing writes with multiple handlers" do
-        skip "ugg"
         ActiveRecord::Base.connects_to(database: { writing: :arunit, reading: :arunit })
 
         conn1_error = assert_raises ActiveRecord::ReadOnlyError do
diff --git a/activerecord/test/cases/fixtures_test.rb b/activerecord/test/cases/fixtures_test.rb
index 0b3aef9f02e0a..4f454fa9912b2 100644
--- a/activerecord/test/cases/fixtures_test.rb
+++ b/activerecord/test/cases/fixtures_test.rb
@@ -1404,11 +1404,11 @@ def setup
 
       handler = ActiveRecord::ConnectionAdapters::ConnectionHandler.new
       handler.establish_connection(db_config)
-      assert_deprecated do
-        ActiveRecord::Base.connection_handlers = {}
-      end
       ActiveRecord::Base.connection_handler = handler
+
       ActiveRecord::Base.connects_to(database: { writing: :default, reading: :readonly })
+
+      setup_shared_connection_pool
     end
 
     def teardown
@@ -1428,15 +1428,76 @@ def test_uses_writing_connection_for_fixtures
     end
 
     def test_writing_and_reading_connections_are_the_same
-      if ActiveRecord::Base.legacy_connection_handling
-        rw_conn = ActiveRecord::Base.connection_handlers[:writing].connection_pool_list.first.connection
-        ro_conn = ActiveRecord::Base.connection_handlers[:reading].connection_pool_list.first.connection
-      else
-        rw_conn = ActiveRecord::Base.connection_handler.connection_pool_list(:writing).first.connection
-        ro_conn = ActiveRecord::Base.connection_handler.connection_pool_list(:reading).first.connection
+      rw_conn = ActiveRecord::Base.connection_handler.connection_pool_list(:writing).first.connection
+      ro_conn = ActiveRecord::Base.connection_handler.connection_pool_list(:reading).first.connection
+
+      assert_equal rw_conn, ro_conn
+    end
+
+    private
+      def config
+        { "default" => default_config, "readonly" => readonly_config }
+      end
+
+      def default_config
+        { "adapter" => "sqlite3", "database" => "test/fixtures/fixture_database.sqlite3" }
+      end
+
+      def readonly_config
+        default_config.merge("replica" => true)
+      end
+  end
+
+  class MultipleFixtureLegacyConnectionsTest < ActiveRecord::TestCase
+    include ActiveRecord::TestFixtures
+
+    fixtures :dogs
+
+    def setup
+      @old_value = ActiveRecord::Base.legacy_connection_handling
+      ActiveRecord::Base.legacy_connection_handling = true
+
+      @old_handler = ActiveRecord::Base.connection_handler
+      @prev_configs, ActiveRecord::Base.configurations = ActiveRecord::Base.configurations, config
+      db_config = ActiveRecord::DatabaseConfigurations::HashConfig.new(ENV["RAILS_ENV"], "readonly", readonly_config)
+
+      handler = ActiveRecord::ConnectionAdapters::ConnectionHandler.new
+      assert_deprecated do
+        handler.establish_connection(db_config)
+        ActiveRecord::Base.connection_handlers = {}
       end
+      ActiveRecord::Base.connection_handler = handler
+      ActiveRecord::Base.connects_to(database: { writing: :default, reading: :readonly })
+
+      setup_shared_connection_pool
+    end
+
+    def teardown
+      ActiveRecord::Base.configurations = @prev_configs
+      ActiveRecord::Base.connection_handler = @old_handler
+      ActiveRecord::Base.legacy_connection_handling = false
+    end
+
+    def test_uses_writing_connection_for_fixtures
+      ActiveRecord::Base.connected_to(role: :reading) do
+        Dog.first
+
+        assert_nothing_raised do
+          ActiveRecord::Base.connected_to(role: :writing) { Dog.create! alias: "Doggo" }
+        end
+      end
+    end
+
+    def test_writing_and_reading_connections_are_the_same_with_legacy_handling
+      writing = assert_deprecated { ActiveRecord::Base.connection_handlers[:writing] }
+      reading = assert_deprecated { ActiveRecord::Base.connection_handlers[:reading] }
+
+      rw_conn = assert_deprecated { writing.connection_pool_list.first.connection }
+      ro_conn = assert_deprecated { reading.connection_pool_list.first.connection }
 
       assert_equal rw_conn, ro_conn
+    ensure
+      ActiveRecord::Base.legacy_connection_handling = @old_value
     end
 
     private
diff --git a/activerecord/test/cases/helper.rb b/activerecord/test/cases/helper.rb
index 002a5e77e75c7..bafe808d7ef64 100644
--- a/activerecord/test/cases/helper.rb
+++ b/activerecord/test/cases/helper.rb
@@ -150,26 +150,9 @@ def disable_extension!(extension, connection)
 end
 
 def clean_up_legacy_connection_handlers
-  handler = ActiveRecord::Base.default_connection_handler
-  assert_deprecated do
-    ActiveRecord::Base.connection_handlers = { ActiveRecord::Base.writing_role => handler }
-  end
-
-  handler.connection_pool_names.each do |name|
-    next if ["ActiveRecord::Base", "ARUnit2Model", "Contact", "ContactSti"].include?(name)
-
-    handler.send(:owner_to_pool_manager).delete(name)
-  end
 end
 
 def clean_up_connection_handler
-  handler = ActiveRecord::Base.connection_handler
-  handler.instance_variable_get(:@owner_to_pool_manager).each do |owner, pool_manager|
-    pool_manager.role_names.each do |role_name|
-      next if role_name == ActiveRecord::Base.default_role
-      pool_manager.remove_role(role_name)
-    end
-  end
 end
 
 def load_schema