Event -> Find Participants displays event id, not event name in event name field
This is related to a general issue with updating CiviCRM under Joomla in a non-US environment, where the views are not updating correctly.  The error was only flagged up when I tried to create an event.  This pointed me to the log file that then showed what the issue was.

I solved the issue by adding the following lines to the definition of, in our case, the view civicrm_uf_group_en_GB:

   `civicrm_uf_group`.`frontend_title_en_GB` AS `frontend_title`,
    `civicrm_uf_group`.`cancel_button_text_en_GB` AS `cancel_button_text`,
    `civicrm_uf_group`.`submit_button_text_en_GB` AS `submit_button_text`


It seems that the update process isn't applying that change.  My knowledge of the update process isn't sufficient to work out how to do it automatically.