Step 1: Still in the Roundcube page of your Webmail, click on Address Book.
Step 2: If you want to export contacts individually, click on each contact and click Export which is located at the left hand corner of your Webmail page.
Step 3: Click on Export selected. On the other hand, if you want to export all the contacts from your address book, click on Export and select Export all.
Step 4: A CSV file will be saved in your computer which is most likely located at your Downloads folder.
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