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In order to "add" Tests to a folder:
Step 1: Click Right click on the folder.
Step 2: Use the context action Add TestsMove into.
Step 3: Choose the Tests you want using the provided filters, a previously saved filter, or by JQL.
Note: If you try to add non-Test issues or Tests that are not part of the Test Plan (e.g., by using a saved filter), an error message will be displayed.
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