[capink]

After adding the tweak and restarting, do the following:

• Add the following custom action:
  

  from calibre import prints
  from calibre.constants import DEBUG
  
  from calibre_plugins.action_chains.actions.single_field import SingleFieldAction, get_possible_cols
  
  class SingleFieldActionModified(SingleFieldAction):
  
      name = 'Modified Single Field Edit'
      support_scopes = True
  
      def run(self, gui, settings, chain):
          db = gui.current_db
  
          col_name = chain.chain_vars.get('_variant_argument')
          if col_name in get_possible_cols(db):
              settings['value_type'] = 'prompt'
              settings['col_name'] = col_name
              SingleFieldAction.run(self, gui, settings, chain)
          else:
              prints(f'ERROR: column name ({col_name}) is not valid')
  
  
      def validate(self, settings):
          return True
  
      def config_widget(self):
          return None

  This action is a modification of the single edit that will let you edit at runtime a column. It reads the column name from a chain variable.
• Create a chain and add the action just added above (Modified Single Edit)
• In the Add/Modify Chain dialog, double click the chain > Chain Variations > add the following template
  

  program:
      columns = 'title,authors,tags,#genre';
      for col in columns:
          add_chain_variant('Edit ' & col, col, 'The name of the submenu')
      rof

  Change the columns variable to include the custom columns you want.

Now you should have a submenu with multiple chain variants, for each column you want.