You can create both folder and project components directly within the subcomponent section, you don't need to navigate to the Components section to create project components.
Creation of Folders
First, you need to click on the Create Folder button at the top right of the page.
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(Create Folder Dialog Screenshot)
Creation of Real Components
You can create a real component from JIRA's own "Component" screen or directly inside the Subcomponents screen. To create a subcomponent inside Subcomponents screen press the Create Component button next to the "Create Folder" button.
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