class CKEditor5::Rails::Context::PresetBuilder

def initialize(&block)
  @config = {
    plugins: []
  }
  instance_eval(&block) if block_given?
end

def initialize_copy(source)
  super
  @config = {
    plugins: source.config[:plugins].map(&:dup)
  }.merge(
    source.config.except(:plugins).deep_dup
  )
end