To install mafft do the following.

1. download deb package from [[https://mafft.cbrc.jp/alignment/software/linux.html|here]]

2. Create a folder to extra the package into.
  mkdir extracted
3. Then unpack
  dpkg-deb -x mafft_7.520-1_amd64.deb extracted/
4. cd into the extracted/usr folder and copy everything to /home/.hub_local/.
  cd extracted/usr
  cp -rf * /home/.hub_local/.

That should do it.