Dear Maintainer,

recently, one of our users noticed that the moderation web-interface no
longer contains the icon for e-mail preview.
This is a considerable limitation on the usability, since non-technical
users often rely on the webinterface to perform moderation of their
lists.

I found that the icons for the moderation preview are loaded from
font-awesome, which fails to load in the browser with the current
version of the package, because of an incorrect
URL.
This results from the outdated version of font-awesome contained in the
fonts-font-awesome package, which is used to provide font-awesome for
sympa. The package still provides font-awesome v4, sympa depends on
version 6 currently.

This should be an easy fix, just include a current version of
font-awesome in the package.

Kind regards,
Sven