Jira offers several built-in conditions, validators, and post functions that help you configure workflows. However, these native tools are often not enough for automating processes using workflows. Jira Misc Workflow Extensions (JMWE) and its 40+ point-and-click post-functions, conditions, and validators, you can quickly configure thousands of sophisticated use cases. You can find all these extensions right within Jira's list of post-functions, conditions, and validators.
Check out this cheat sheet, available at innovalog.com/cheatsheet, with all of the Jira & JMWE extensions available to you.