Everyone can find a way to open a new tab in Vivaldi that fits their habits. You can click the + button on the Tab Bar, go through the main menu, or use one of the many shortcuts. But there’s another lesser-known option.

When you have the Tab Bar on the side of the window or at the bottom, you can just double-click on an empty area on the Tab Bar and a new tab will open. When you have the Tab Bar on top, then a double-click will maximize the window or revert it to its previous size, but you can get double-clicks to open new tabs on a top positioned Tab Bar when you turn on Native Window from Window Appearance settings.