Favicons for specific AUIDs and From addresses

[lieser]

Favicon were added so that the user can directly link the sender of an e-mail to a company, without necessarily needing to carefully check the signing domain and from address.
As currently favicons can only be shown for whole domains, this means that e-mail provider can not be added to the list (unless they use a separate domain for their employees and official e-mail addresses).

Adding the possibility to do show favicons also for specific AUIDs and From addresses would change this. The add-on could show the favicon only for official e-mails (e.g. support@e-mail-provider.example or employee_name@e-mail-provider.example with AUID set to employee@e-mail-provider.example).

[lieser]

Adding favicons for specific from addresses or AUIDs is now possible. Note that the from address must be in the SDID.

This is not intended to support the in my opinion bad practice where newsletter are only signed by a used third party sender of newsletter, and not in addition by the domain on which behalf the newsletter is send.