Vivaldi is one of the best browsers for desktop and Android. It comes with lots of customization options and better theme support. Vivaldi latest snapshot update 3.3.2022.6 for Windows addressed an issue where users may not be able to distinguish between normal and private windows.
Vivaldi automatically colors the browser window with the website/page you visit. Although Vivaldi offers visual clues to your Private window, such as separate intro page and black color address and search bar to separate from the normal window, sometimes it is difficult to recognize what is private or normal when both are open.
“Our theme support is second to none, but allowing seemingly endless ways to color your windows comes at a price for some users. Aside from certain hints in the address bar, which can be hidden, it can be difficult to distinguish between normal and private windows. So we are offering even more options.”
Vivaldi now has new themes available for private windows with a new one enabled by default.
And you can choose from Vivaldi, Human, Hot Pink, Subtle, Dark, Blueprint, Beach and Light available by visiting settings > Themes > Private Window Theme.

We are introducing a new “private” theme (applied by default) and also the ability to set unique themes for normal and private windows.”
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