Where can I find all supported workflow triggers to check whether the plugin I am using is supported?
All Workflow Triggers available readily can be seen under the Triggers dropdown. If you want to use triggers related to a specific plugin, e.g., WooCommerce, make sure the plugin is activated.
note
Currently, only the WordPress triggers, i.e., User related, available with the free version and you should be a paid user to get access to other triggers.