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cat certificate.crt ca_bundle.crt > full_chain.crt
openssl pkcs12 -export -out certificate.p12 -inkey private.key -in full_chain.crt
The export password (and import password later) should be inputted here
On Windows:
(copy the certificate files to C:\Program Files\OpenSSL-Win64\bin and run cmd as administrator at that folder path)
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