diff --git a/app/models/concerns/has_custom_fields.rb b/app/models/concerns/has_custom_fields.rb
index 3662c4534f6..6174bd13a9d 100644
--- a/app/models/concerns/has_custom_fields.rb
+++ b/app/models/concerns/has_custom_fields.rb
@@ -114,7 +114,9 @@ module HasCustomFields
       get_custom_field_descriptor(key).append_field(target, key, value)
     end
 
-    def register_custom_field_type(name, type, max_length: DEFAULT_FIELD_DESCRIPTOR.max_length)
+    def register_custom_field_type(name, type, max_length: nil)
+      max_length ||= DEFAULT_FIELD_DESCRIPTOR.max_length
+
       if Array === type
         Discourse.deprecate(
           "Array types for custom fields are deprecated, use type :json instead",
diff --git a/lib/plugin/instance.rb b/lib/plugin/instance.rb
index 4346f1caf46..35acf3e5a1d 100644
--- a/lib/plugin/instance.rb
+++ b/lib/plugin/instance.rb
@@ -552,28 +552,38 @@ class Plugin::Instance
   end
 
   # Applies to all sites in a multisite environment. Ignores plugin.enabled?
-  def register_category_custom_field_type(name, type)
-    reloadable_patch { |plugin| Category.register_custom_field_type(name, type) }
+  def register_category_custom_field_type(name, type, max_length: nil)
+    reloadable_patch do |plugin|
+      Category.register_custom_field_type(name, type, max_length: max_length)
+    end
   end
 
   # Applies to all sites in a multisite environment. Ignores plugin.enabled?
-  def register_topic_custom_field_type(name, type)
-    reloadable_patch { |plugin| ::Topic.register_custom_field_type(name, type) }
+  def register_topic_custom_field_type(name, type, max_length: nil)
+    reloadable_patch do |plugin|
+      ::Topic.register_custom_field_type(name, type, max_length: max_length)
+    end
   end
 
   # Applies to all sites in a multisite environment. Ignores plugin.enabled?
-  def register_post_custom_field_type(name, type)
-    reloadable_patch { |plugin| ::Post.register_custom_field_type(name, type) }
+  def register_post_custom_field_type(name, type, max_length: nil)
+    reloadable_patch do |plugin|
+      ::Post.register_custom_field_type(name, type, max_length: max_length)
+    end
   end
 
   # Applies to all sites in a multisite environment. Ignores plugin.enabled?
-  def register_group_custom_field_type(name, type)
-    reloadable_patch { |plugin| ::Group.register_custom_field_type(name, type) }
+  def register_group_custom_field_type(name, type, max_length: nil)
+    reloadable_patch do |plugin|
+      ::Group.register_custom_field_type(name, type, max_length: max_length)
+    end
   end
 
   # Applies to all sites in a multisite environment. Ignores plugin.enabled?
-  def register_user_custom_field_type(name, type)
-    reloadable_patch { |plugin| ::User.register_custom_field_type(name, type) }
+  def register_user_custom_field_type(name, type, max_length: nil)
+    reloadable_patch do |plugin|
+      ::User.register_custom_field_type(name, type, max_length: max_length)
+    end
   end
 
   def register_seedfu_fixtures(paths)