How did they reach that figure? $1.4 billion dollars seems like far too much.
Edit: Interesting. Their methodology talks about rewriting all the state's public-facing server side applications to be open source. (Hence the cost.)
I thought the bill was just requiring that the public be able to use libre browsers and apps on their own devices to access state services, not that the state's server code had to be open source.
The problem with doing it this way is you're accounting for the bill as the cost of upgrading all government systems [to non-proprietary ones], which is on the same order as the cost of upgrading all government systems in general -- something that happens eventually but on its own budget.
So require upgrades to be to non-proprietary systems. Then you just wait. In maybe ten or fifteen years pass a bill requiring any remaining proprietary systems to be replaced, which by then will be fewer of them and by then will be the ones that most need to be replaced.
[0] https://gencourt.state.nh.us/lsr_search/billText.aspx?id=188...
Another comment mentions fillable PDFs not working in non-Adobe software. This seems like the most likely culprit to me. And in general, if someone has to go back over the entire surface area of an application and re-test everything to find all the quirks like this, I can start to understand how that huge cost estimate might make sense.