Use BIMI to get favicon

[se4n01]

Hi,

I think it would be a good addition instead of shipping a DB of valid favicons (which is very arbitrary) if you use the BIMI standard to downloads the icon for BIMI aligned domains.

https://datatracker.ietf.org/doc/draft-brand-indicators-for-message-identification/

Best wishes,

Sean

[zWhdmB5T]

Please have a look at add BIMI icons support (instead (?) on favicon) [enhancement]

[lieser]

It certainly would be nice to no longer have to ship a DB of valid favicons (and more importantly maintain it). Although I don't yet see BIMI as a complete replacement it could certainly at least reduce the number of entries needed to be added to the internal DB.

Like @zWhdmB5T pointed out the add-on already has some BIMI support. It relies on the MTA to write the BIMI result inside the Authentication-Results header. See also https://github.com/lieser/dkim_verifier/wiki/Display-Options#show-the-favicon-of-known-signing-domains-before-the-from-address.

Note that I also explicitly don't want to support the easier to implement self-asserted logos of BIMI. See #417 (comment) for a longer explanation on why.

What could probably be added is local verification for Verified Mark Certificates (VMCs) and Common Mark Certificates (CMCs) (see also https://bimigroup.org/understanding-bimi-certificate-types/). I just created a new issue to track this #543.

BIMI (including the self-asserted logos) could also be used for a fancy way to implement #83.

I will leave this issue open for now as a reminder to improve documentation on what parts of BIMI we currently support.

[se4n01]

Thanks very much for the thoughtful response. I completely agree with your approach and comments regarding trust.