I really like Opera GX, but I think needs two features already available in opera one.

The first one is the option to hide the sidebar, and show it when the cursor approaches the side of the window, and the second one is the split tabs.

And if opera really wants to reach the top level, it would be to make it possible to customize more these two features. Like move the sidebar to the right, and split the tabs not only in vertical, but horizontally as well, or maybe a combination using quadrants. Maybe it's complicated, but it will be really great for different screens resolutions.

I really hope these two features come to Opera GX