First, please don't see this as a rant. I've used Opera for years and liked it very much, and for that reason I think devs deserve to know why I'll stop using it.
Sadly opera lost features after features that made it innovative, customizable, and a pioneer browser to the point that I see no advantages for using it. Also, recent changes failed to fix issues with compatibility and made many new problems (outlook web app, twitch, etc). Opera is an old enough browser that you should expect things like that to just work. Bookmarks are the best example. I still need to connect to a webpage to see my old bookmarks that were removed from where they were?? and from that page, last time I checked, there is no clear way to export them or convert them.
For all that Opera did for me I could've lived with that, but the thing that was too much was the speed dial. Today I opened Opera to find MY speed dial changed. I never asked for the booking and amazon and whatnot icon from your parters. I was never asked, never offered, it was there, forced on me. I'm sorry but this is not behavior that I support. I hope to revisit Opera in the future, but for now, I'm trying Vivaldi.
Wish you the best, goodbye