In order to add OpenPGP public key from Public key servers. Go to Settings -> Messages -> Encryption:
1. Click on Add public key.
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2. Click on Search in public key servers.
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- Write down the email ID of your contact person and click on Search.
- This will search your contact person OpenPGP public key via WKD method.
- If the key is not found using WKD method, then the search will be made on keys.openpgp.org server (check their privacy policy).
- Select the right public key and click on Import.
Note: Keys with no User ID (display name and/or email address) are presently not processable on our side. We plan to address this in future.
You can also import key using file or text. See also this blogpost.