To add a post function to a transition:
1. Select the Jira icon > Jira settings > Issues.
2. Click Workflows and then Edit for the relevant workflow.
3. Select the transition:
In diagram mode, select the transition arrow.
In text mode, select the transition's name from the Transitions (id) column.
4. Open the post functions tab:
In diagram mode, click Post functions in the properties panel to show the triggers configured for the transition.
In text mode, select the Post functions tab.
5. Click Add post function.