Great. Information about the possibility of using Chrome extensions is awesome!
And with this it sounds like it really worth giving a try - thank you so much for the useful tips

Thanks a lot Lem729 for the trick about Chrome extensions, didn't know that.

Those extensions might solve the problem, but I have to try them. It seems that they are separate windows? - That is not the most elegant solution

After so many time, I'm done. I was waited for long long time for the totally simple thing like side panel, which was one of the best features Opera had. Because of that and many perfect solutions, I was really a big Opera fan, but now, seeing that so many things are not working in 12.17 version (last one, from yesterday was completely mixed up LinkedIn page), I'm done, transferring to FireFox.

Maybe some will ask why I don't use newer versions. Reason is one and simple. There are no Panels (sidebar panels, or side bar, call it as you want). That was a perfect solution for the organization of almost everything. I read lot of posts, with not so intuitive explanations why it can't be introduced again, so than I decided to keep old, V12, but now, when there is more and more unsuitabilities and sites I can't wait any longer.

Of course, I will check for new versions from time to time, but for now... I'm quite sorry

[Topic closed as a duplicate of:
https://forums.opera.com/topic/894/opera-desktop-panels]

Exactly everything what tgaal wrote stands for me. It is something pretty wrong if you have so many post of long time users who are simply sad because they have to use now quite old versions, while the new one appear to miss functionalities which made me to use Opera as a most favorable browser in the first place. I am not a developer, I am simply the user. And I will use Opera for some more time, hoping that some of normal, useful appeals from long time users catch attention.

In the recent days, any video on youtube I try to display in resolutions over 360 just stops and there is nothing but dark screen, not dependable with full screen or usual. It is not happening with other browsers nor it is connected with Internet speed (cable net). I use V12.16, so I tried the new versions of opera, but it is the same

Any tips?