Note for Firefox 70.0.1 users

Firefox rolled out a point release, 70.0.1, that fixes a major problem (browser crashing when the Site Bleacher add-on is installed in my case, or perhaps any storage cleaner that cleans indexed db storage).

For those that toggled dom.storage.next_gen to false in order to work around the problem, you can go ahead reset that pref in about:config and remove if from your user.js/user-overrides.js if you added it there.