To export your Bitcoin addresses from Bitcoin Core safely, follow these steps:
Exporting your Received Addresses as CSV
1. Open up your Bitcoin Core application.
2. In the main menu, select File > Receiving addresses...
3. Here you will see all of the addresses you have created to receive transactions. Click on the "Export" button to save these addresses as a CSV file.
Uploading the CSV file to your portfolio
1. Go into your CryptFolio and Configure the portfolio you wish to add the addresses to.
2. Click on the "Address" button to add a collection of addresses.
3. Copy the contents of your exported CSV file into the text field, or upload the file using the system dialog. Make sure to also set the currency you're uploading addresses for to Bitcoin.
4. Click "Upload Addresses" to submit the file. CryptFolio will now process the file and add the addresses to your portfolio.
5. You're done!
Are some addresses missing?
You may be missing some other addresses from your export, which Bitcoin Core by default does not expose in the Receiving Addresses export. To get these, follow this guide to export your change and keypool addresses.