This is because installing bcmwl causes man-db triggers to be run, which in turn queries debconf. As ubiquity already has the debconf database locked, this fails.
The optimal solution, as suggested by cjwatson in #ubuntu-installer, is to use passthrough.
This is because installing bcmwl causes man-db triggers to be run, which in turn queries debconf. As ubiquity already has the debconf database locked, this fails.
The optimal solution, as suggested by cjwatson in #ubuntu-installer, is to use passthrough.