This browser is almost perfect: something I think is incredibly handy from other browsers (see Microsoft Edge: Collections) that could be easily implemented in Opera GX is a panel for bookmarks on the hot bar that is collapsible, and when opened displays different folders that show previews of chosen webpages. within them; it would be most convenient if this panel stayed open from tab to tab for ease of adding to it until manually closed. I've found this to be extremely useful and less cluttered than traditional bookmarking methods.