Today we would like to promote Opera 58 to the beta stream. We are happy to announce that this build, based on chromium 71, comes with a new feature. Opera 58 will warn you before closing a window with multiple tabs. This means it will prevent you from accidentally losing the data you might have typed in when filling out forms or writing comments.
Opera 58 beta warns you before you close a browser window with multiple open tabs
The confirmation dialog we added is there to warn you before you close an Opera browser window with multiple open tabs. If you don’t want this window to appear, simply tick the checkbox titled “Do not show this warning again”.
This dialog will not be shown when closing private windows.
To turn the warning back on, go to Settings > Advanced > User interface.
Chromium was updated to 71.0.3578.75 version.
The full changelog is here.