I use TreeStyleTab [1] and usually have more than 150 tabs at the same time on my PC and around 60-100 on my professional computers (at home and at work). I sort them by category, then when I have a spare day I read dozens of news one by one, or when I'm in a mood, I read by categories what I like. In the last 3 years I tried to switch to Opera and Chome a few times, but they... they just suck for my requirements. Firefox lets you search by bookmark, history and open tabs, which is really useful in my cases (I also have hundreds of bookmarks).

[1] https://addons.mozilla.org/en-GB/firefox/addon/tree-style-ta...