Normally I do not allow remote contents. They are not embedded in the email, and they need to be downloaded from a remote server. So if you allow, the server will know something about you.

If you select allow, Thunderbird will remember your selection for future emails - that's the preference.

Thanks. yes I see you are guessing to. I believe the first sections are more or less clear but apparently there is a difference between in this case

"...remote content from all 5 origins listed" and "...remote content for ron@ronor.ch"

The diference could be anything. It is not clear from the message but the developer/system designer had something on the whiteboards making this distinction. As it is not documented, as far as I know hence my question the user has to guess.

If nobody is able to point to a document describing this I will file a request at bugzilla.

https://support.mozilla.org/en-US/kb/remote-content-in-messages

I wonder if deepseek is right here: https://chat.deepseek.com/share/74jmkvszzkr2jo3ntd

1. Individual origins → fine-grained control, one URL at a time.
2. All 5 origins → batch approval of those 5 only.
3. Sender-based rule → blanket approval for everything that specific sender includes now or in the future.

Which would mean in the last case whenever ron@ronorp.com decides to add insta/tiktok/amazon-tracking to future emails they will be silently accepted. Is that a right assumption?