Flush Wideget Cache

That check may be overly broad. It’s specifically referring to the flush_widget_cache() function in the Recent Comments widget. That function was removed entirely, because the comments system was revamped and flushing that particular cache is no longer necessary.

Hi,
Thanks for your answer.
This message appears on every custom widgets, in function __construct(), using this code:

add_action( 'save_post', array($this, 'flush_widget_cache') );

add_action( 'deleted_post', array($this, 'flush_widget_cache') );

add_action( 'switch_theme', array($this, 'flush_widget_cache') );

Not only on Recent Comments Widget… Any ideas ?
Regards.

The check for flush_widget_cache has been removed from the latest version of the plugin on github.