Well:
1. Abrowser is basically just a rebranding of Firefox. It would be completely
pointless for it to be in Debian.
2. Trisquel doesn't get updates downstream from Debian in time, so putting a
Web browser in Debian and waiting for it to flow downstream would result in
an old version with security patches from Canonical if they were lucky, or
more likely, just an old, insecure version. Considering that Ruben is a
developer of IceCat, this wouldn't make much sense.
3. It's an additional maintenance burden. The few people contributing to
Trisquel are busy enough as it is.
