code: func (f FolderConfiguration) RequiresRestartOnly() FolderConfiguration {
  	copy := f
  
  	// Manual handling for things that are not taken care of by the tag
  	// copier, yet should not cause a restart.
  	copy.cachedFilesystem = nil
  
  	blank := FolderConfiguration{}
  	util.CopyMatchingTag(&blank, &copy, "restart", func(v string) bool {
  		if len(v) > 0 && v != "false" {
  			panic(fmt.Sprintf(`unexpected tag value: %s. expected untagged or "false"`, v))
  		}
  		return v == "false"
  	})
  	return copy
  }
docs: // RequiresRestartOnly returns a copy with only the attributes that require
  // restart on change.