Yes, on my Debian 8.0 system (i7 32G ram) the window is annoying. It's working differently than the whole system. Please dear developers use, the system's wm. My system is not bringing a window to the top when it focused. Not even when I click inside the windows. Only border and title click brings windows the front, and I like it this way. There are some minor bugs, but I understand it is just a preview. Go Vivaldi!
The black death issue (the program starts with an empty black window):
My way: F11 twice! (Full screen, and back)
Maybe I used strange wording beat Opera and Chrome
I am more questioning the starting point. Start developing another browser on chromium … a bit better than using mozilla Why not starting from scratch or start from where Presto left the game?
1. Presto is not open source. It does not belong to them and nobody can use it. Opera never open source it exactly for that reason, so no clones or forks would be made. So that answers your why.
2. Vivaldi is a team of 30 persons, not hundreds of developers or even thousands like other browsers. No time !!!
3. Nobody would code for a niche engine that only has a couple of users worldwide. Everyone will code for Webkit/Blink. At the end of the day you want a browser that works with your websites. Presto never did.
4. Who is going to give Vivaldi the billions to do it? You will? How much did you pay so far or donated to Vivaldi? You do realize the owner is spending his personal money into this company and so far they had no profits. Be realistic. Its a start-up not a multi-billion company, not even Opera could mass market their own rendering engine, they lost.
5. Why in the world re-invent the wheel. That is dumb. Just use what you have right now.
When you create a tab stack, you'll see 2 (or more) thin bars above the new tab stack. Clicking those will switch to whichever tab you'd like.
this was one of the first things, that I've tried, but it doesn't do anything. Neither in Ubuntu, nor in Win7
Not sure what you mean by "proper bookmark management", Vivaldi seems to do it's job much better than Firefox in this departament.
I may have missed something but Vivaldi does not appear to have a right-click Sort By Name feature in bookmarks.