Notice URL (Incoming Webhook URL) <%= text_field_tag 'settings[notice_url]', @settings[:notice_url], size: 80 %>

Set Notice URL for each project? <%= check_box_tag 'settings[notice_url_each_project]', '1', @settings[:notice_url_each_project] == '1' %> If you checked, you will set the Notice URL for each project. Create and set a <%= link_to 'project custom field', { :controller => 'custom_fields', :action => 'new', :type => 'ProjectCustomField', :custom_field => { :name => 'Assign Notice URL' }} %> named "Assign Notice URL" (without quotes).

Mention to assignee?
(Except when you assign yourself) <%= check_box_tag 'settings[mention_to_assignee]', '1', @settings[:mention_to_assignee] == '1' %> Mention using the ID set in the user custom field. To use it, create a <%= link_to 'user custom field', { :controller => 'custom_fields', :action => 'new', :type => 'UserCustomField', :custom_field => { :name => 'Assign Notice ID' }} %> named "Assign Notice ID" (without quotes).
For Slack, specify a member ID. For Rocket.Chat, specify a Username. For Google Chat, specify a user ID.

Disable sending description and notes? <%= check_box_tag 'settings[disable_sending_content]', '1', @settings[:disable_sending_content] == '1' %> If you checked, the issue description and notes will not be included in notices.