Yes. But the state still has to prove that what you did was a) a Nazi thing and b) that you either knew or should have known it was so.
So if you show the Hitler salute, you'll be arrested and fined. If you give a speech in which you suggest that immigrants need to learn "the liberating power of work" (referencing the Motto of Auschwitz "Arbeit macht Frei" "Work makes Free") that is totally fine.
I'm not going to tell you that you're managing your information wrong. I would physically die if I had ever more than 20 tabs (my ADHD couldn't handle it).
But I think you might be using the wrong tool. A browser (like Firefox) is not really designed as an information manager. It's primary purpose is navigating and visualizing web pages. So when you talk about "a few megabytes of text and images" thats not what your browser sees. Your browser handles more than just the text and images. It also handles fetching and prefetching, a browser history for every tab, a JS context and much much more.
What you want is some kind of personalized archiving system that processes websites into machine processable (ie searchable) structures. Firefox is not that. Maybe data hoarder communities will have the answers you seek.