I have a very strange problem with a sent HTML file.
The HTML file contains java-script (longer then 2048 character a row). The encryption and decryption successfully worked, but the decrypted file didn't work.
After the drcyption the file got a line break after 2048 characters, so the javascript is corrupt.

Sender is the ciphermail gateway
Version: 4.8.0-0
Built: 2020-05-19-13:37

Receiver is K-9 with OpenKeychain or Thunderbird with integrated PGP.
So I think the "problem" is in ciphermail.