Bring back the quickmenu button that was next to the search bar and the refresh button. It was such a good button, bring it back!
And secondly make on the tabs "x" button larger, because right now it is a pain to close the tabs with such a little "x"!

Opera One. (Didn't even know there are more versions).

update:
The sidebar is in pinned mode and looks like this:

When I open opera 2 times (2 different instances), then on the 2nd instance, after a while of using the sidebar messenger app, it just stops working, doesn't work, and even more clicking on it crashes and restarts opera

Bring back the quickmenu button that was next to the search bar and the refresh button. It was such a good button, bring it back!
And secondly make on the tabs "x" button larger, because right now it is a pain to close the tabs with such a little "x"!