hook_civicrm_searchTasks get invoked twice for some entities

When your extensions implemets hook_civicrm_searchTasks and in case you did a participant search page then in the result page, the action you added via this hook will appear twice in the actions box :

This happens because the hook_civicrm_searchTasks hook get invoked twice for each extension when Search Participates result page get opened ..

The reason why it does not happen at contact page is because the code that generate the menu items list will not call the hook if the menu items are already set , see :
https://github.com/civicrm/civicrm-core/blob/master/CRM/Contact/Task.php#L253
https://github.com/civicrm/civicrm-core/blob/master/CRM/Contact/Task.php#L80

Unlike Event class which call the hook even if the tasks are already set :
https://github.com/civicrm/civicrm-core/blob/master/CRM/Event/Task.php#L70
https://github.com/civicrm/civicrm-core/blob/master/CRM/Event/Task.php#L150

from looking into the code , these entities should suffer from the same issue but I didn't test that though :

• Campaign
• Case
• Contribute
• Grant
• Member
• Pledge