More recently, I have started to use also Vivaldi, but alongside Firefox and Chromium and I cannot delete any of them, because there are things for which one is better than the other 2.

For Vivaldi, the main reason why I use it is its "Print" command. The "Print" command of Vivaldi produces decent PDF files in most cases, which include all or most of what is rendered by the browser on a display.

In contrast with Vivaldi, the "Print" commands of both Firefox and Chrome/Chromium are extremely buggy and they very seldom produce an output file comparable in quality with what they render on a computer display (i.e. they typically overlap various things that should not be overlapped, making some of them invisible; juggling with page sizes and orientations may alleviate the problem, but seldom eliminate it completely).

The second thing that I like at Vivaldi is the user interface with mouse gestures. Mouse gestures are unfortunately seldom used by most programs, despite the fact that such a user interface is much faster and much more comfortable than using buttons, icons, toolbars, right click menus etc.

I am using Vivaldi on Linux and I do not know whether what I see is something specific to my configuration or it is generally valid for Linux. I have tried 4 or 5 Vivaldi versions, but all have the same bug. They work perfectly the first time, but the second time they remain stuck at start, without being able to open their main window.

The workaround that I use for this bug is that before restarting Vivaldi I delete everything in ".config/vivaldi/Default/" and I copy back there some saved copies of the files "Bookmarks" and "Preferences". Then Vivaldi works OK, so the problem is that it saves some corrupt data in one of its configuration files, but I have not bothered to identify which is that file, because I do not want to preserve anything from a session besides the bookmarks and the preferences.

On my computers, Vivaldi also shares a bug (feature?) with Chrome/Chromium, being derived from the same code base. Around a couple of years ago, Chrome/Chromium has begun to have a delay of about a couple of minutes at start, before opening its window. Now Vivaldi has the same behavior. I believe that this is caused because since that time Chrome/Chromium attempts to contact at startup some servers on the Internet, but those are likely to be blocked for some reason by my firewall. The browser waits for a response until some timeout expires, and it starts the normal operation only after giving up.

Workspaces to organize tabs, gestures + layout customizations are all great