There's a little detail with VIvaldi, sometimes when I minimize it, happens that is like the system try to impose its own window over Vivaldi one (Sorry for not explain with much detail, it just that this is the first time I saw something like this, also the english is not my main language).
Here is a picture of the problem.
I'm not sure why this is happening. What you are seeing is two sets of window decorations (the fancy term for the top bar on each window). Vivaldi is special because it has its own window decorations that do not conform to Marco/MATE's built in ones.
Unfortunately I haven't been able to find a solution for things like this. Firefox can use regular window decorations as well as GTK3, and Chrome and several Chrome based browsers like Brave can do the same. But I haven't seen this particular bug, you could create a Marco rule that undecorates vivaldi windows, if that is possible.
Hopefully just the notion that what you are seeing is duplicate Window Decorations will help guide you towards an answer.
Thanks, I would look further from that point. It really surprised me because I used to use Opera (which also have it’s own window decoration) and this never happen.
