Documentation

In the schematic menu "Components":

Image: Export all components of the project to the component database and put them on list there.

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Result for the project DicePCB:

Image: Components of the project DicePCB exported to the component database and (automatically) put on list.

However, in a project without a schematic, there is no schematic menu components. Instead, proceed as follows: In the layout, click on a desired package at its handle cross to select it. Now press the 'x' key to export it to the database. One at a time.