Let it simplify, let it simplify
Most solutions involve simplifying the situation, or avoiding the temptation to add complexity. Make it simple or keep it simple. Mind your own business, don't start fights, don't buy unnecessary stuff, don't get into situations where Deepstate can tangle you in red tape.
Sometimes you have to discover these simplifications by accident. I didn't realize the evil addictive power of TV until lightning knocked out my cable box in 2010. After a week without it, I simply tossed out the whole thing instead of getting a new cable box.
A solution to Firefox's problems came similarly. Firefox has become nearly unusable in the last year or so, constantly crashing when Flash failed. I can't find any way to turn off Flash. Supposedly there are 'switches' in the about:config lists, but they don't work. If your Flash is 'usable', Firefox WILL USE IT, AND WILL CRASH.
Uninstalling Flash from the computer doesn't work, because some important websites won't run at all.
What does work is simply
letting the Flash version grow old. When the Flash in your computer is not the latest version, Firefox avoids it. A warning appears giving you the choice of using it anyway, but everything else still works when you don't say Yes to the choice. Nothing crashes.