When someone forwards content from one place to another, it is helpful for recipients to know from which person or channel the original message was forwarded. Ideally, the name of that person or channel should be displayed, and by clicking on it, users should be taken to the original sender’s profile or channel.
This feature might be more appropriate to enable only for channels by default, but it would also be useful if there were an option allowing users to show their name when forwarding messages.
Actual behavior
Currently, it is only possible to see that a message has been forwarded, but there is no indication of who originally posted or wrote it. There is no visible trace of the original sender or channel, and recipients cannot determine where the content came from.
similar to many other messengers, Delta Chat does not show the source on purpose. this is for privacy reasons, to minimize metadata, but also as the sender could fake these informartion, so without additional e2ee there is no trust anyways.
if the source is important, the sender should just add a hint. this is much more useful, also as the sender can add more information etc.
if you do not have a source or do not trust forwarded content, do not forward further.
Such requests for noting the user and time of the original message is usually out of courtesy (i.e., how citations are expected to be formed on the web), not as a form of authentication.