Dne st 7. října 2020 Michael via tde-users napsal(a):
PS2: Slávek do you know why Bill's (and probably a few others') email address gets included as a CC: when replying [Kmail >> R]? And yet most other people (yours in fact) doesn't. Nothing critical, just annoying to always need to check and delete the extraneous addresses.
Here, it depends on whether the sender has an SPF set for his domain and / or whether the message contains a DKIM signature valid for the sender's domain. To prevent rejection of the post due to SPF violation or due to violation of the DKIM signature, "DMARC mitigation" is performed, where the address of the original sender is moved to CC: and the address of the mailing list is used for the sender.
However, whether the original sender's address will be automatically added to the To: when replying depends on whether the original sender has his address explicitly listed as the Reply-To: header.
Cheers