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In Jira, go to Projects.
Make sure you are on the right project.
Click the Documents tab and navigate to the folder where you want to create the folder.
In the file explorer from your local computer, select the folder(s) and the file(s) that you want to upload as documents and drag them all in the mid-panel of Documents page.
The uploaded files and folders will have the same folder structure as on your local computer, and their Title set to the filename.
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