I needed to make a fancy signatures for some clients, in RoundCube Webmail. For that, I wanted an inline image in a HTML signature – something that is not possible to achieve in current Roundcube. So i made a some changes, and come up with a solution:
Every change is in
\program\steps\mail\sendmail.inc
and \program\lib\stringstream.php is needed.
I am lazy to write this… Finish whenever you want.