Vivaldi[1] is now where most of the Opera founders have congregated to. The project is fresh and rhymes of Opera Presto days.
I still use Opera, and super-apprehensive about this new development. It's still fantastic - the rendering engine change actually benefited Opera, in that it removed so many of the rendering glitches in Opera 12. Some options were lost, but it's still very configurable. I respect Hakum and the team that's still there, but not sure if they'll stick around. It will be a shame if we lose one of the best desktop apps on the planet to spyware/bloatware.
And that's why browser vendors can never win. Too many cases to optimize for; if you don't get every extremely contrived (non) use case right, it's off to twitter/hn-comments-section to complain. FFS
Since Firefox now only reloads tabs on demand after a restart, it's not resource-heavy to keep many tabs open if one occasionally restarts the browser.
I also reserve some time to clean them up about once a week, I start with the oldest tab and "take care of it", sometimes it's just a news story I want to read, sometimes it's something I kept opened because of the information on that page.
If I don't do that I will have a thousand tabs opened and will never actually do anything about it.
I'm home now, and have been online for ~2 hours. Gmail, Twitter, 5 JIRA tabs, 10 Jupyter notebooks, 5 stackoverflow, 2 python doc pages, 1 javadoc page, 2 Wikipedia pages, 2 Kaggle pages, Hacker news.
30 tabs, and I haven't really read any news yet.
That's only Wikipedia. I do the same things with forums, documentation, stackoverflow, etc.