Use the highlighted toolbar button to show / hide the panel which contains new note stacks. Here you can capture description of new Rules, Scenarios etc. and then drag the notes to the right.
Once the notes have been dragged to the right they become part of the Feature file and are persisted when you press the Save button.
Always show new Story notes
By default new story notes stack gets hidden once you have dragged over at least one story note to the right. It can be made always visible via the highlighted editor option menu below.
This is useful when you need to split the current user story into further separate stories. You can temporarily capture the newly split story in the current Feature before creating a new Jira issue and moving it there under its own Feature.
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