Some recipients of my emails see text with no extra line breaks or paragraph breaks so the message is compressed and not readable (no white space). I can only see the issue when they reply and include the original message in their reply.

The same message can go to several recipients and only some have the issue. This was never the case before. Formatting was always perfect for all recipients. I believe this started to happen early in 2025.

Here is my setup:

WinPMail version: Version 4.81.1154, Jan 10 2023, build ID 1154
Language resources: Standard UK English resources (EN,0,LL)
Extension Manager version: 1.14
Operating mode: Standalone
User name and ID: Single-user mode, 0
Windows version: 6.2

Can you please post screenshots of how the original message (i.e. your copy-to-self) and the recipient's view look? And what kind of messages are affected, formatted (HTML) messages or plain text?

And just to clarify one thing: Keeping paragraphs intact always required to insert a blank line between these, especially within formatted messages since HTML converts line breaks to blank spaces by default.

Three screen shots. Original email being composed. Recipient reply that I received. The CC that I received.

X-mailer: Pegasus Mail for Windows (4.81.1154)

Not all clients cast this line in message's headers, especially webmail.

Could also be Linux or Apple since these sytems are using a different kind of line break chars: a single LF or CR as opposed to CRLF which isn't only the Windows line break but also the email message standard.

Noticed one image showed file was sent as rtf format message?
Was that format required for some reason, or was it pasted from some other document or program.

Is the raw message encoded in some way.

Don't know exactly how RTF formats paragraph breaks. What version of Windows and email clients are they using. Trying to see a common configuration on who's is working and who's is not.

The TER component Pmail uses RTF. I think the HTS component converts RTF to HTML but IERenderer also plays along.

RTF is one of those "poorly documented" stuff. IIRC the first visual editors all used RTF encoding text. I still have several RTF-only editors here.

The RAW view is just the Pmail message reader view in RAW text. You can see how the message is coded, from plain-text, HTML, Base64, you named it!