what do you mean no security updates? It just gets them a day late, its
good till 2019. I used to just wait a day to use trisquel if it was serious
then update the next day.
Go to https://www.ubuntu.com/usn/ and then compare your version of the
file. or apt log if it applies to trisquel. I don't have trisquel
installed anymore either cause I'm doing steam gaming now. But I doubt that
would have changed, unless it broke.
The browsers might be a diff story. If they aren't getting updated you might
have to just change to something more mainstream.