I apologize if this has been discussed before.
I use sidebar all the time, especially for WhatsApp. After a recent Opera update, I noticed that the sidebar is now behaving differently than before. Before, when I click one of the icons, the widget window will be shown as a pop-up overlay (?) over whatever page currently showing. But now it acts like a browser window that always open, shown side-by-side with the main current page, so the main browser page gets narrower when the sidebar is being used.
I can only guess that it was changed so that the main browser page always fully visible regardless sidebar, and the sidebar widget/extension can open all the time. I can see how this will to be very useful for some people, but I have to admit that I don't like this and want the old one to return. I don't want the sidebar to be open all the time, and it's jarring to see the page gets squeezed/stretched repeatedly whenever I open and close the sidebar.
Is there an option that I miss somewhere in the Settings page that can change that? If not, I hope Opera would be kind enough to let us choose which mode/behavior that we want.