Persistence preset: additional software
_Originally created by @BitingBird on [#9050 (Redmine)](https://public-redmine-archive.tails.boum.org/code/issues/9050)_
Right now, the additional software feature exists, but it’s not shown in
the persistence configuration. It should be added. When selected, it
should open a windows with warnings (cf
<https://tails.boum.org/doc/advanced_topics/additional_software)> and
let you enter the list of packages you want.
This is the easier version of tails/tails#5996
Team: alan, sajolida, reviewer (?)
### Related issues
- **Related to** tails/tails#5996
issue