Comment 2 for bug 488340

I downloaded from http://us.archive.ubuntu.com/ubuntu/pool/restricted/b/bcmwl/ the downloaded the bcmwl-kernel-source_5.10.91.9+bdcom-0ubuntu5_amd64.deb file to upgrade from the ubuntu4 version that was giving me the problem you describe. Now it seems to be working again, not disconnecting every 5 minutes. This is on a macbook pro 5.2 MBP17. Hope this helps you too.