Developer Søren Hentschel has shared the first mockups of Firefox's upcoming Nova design language, which will replace the current Proton interface with rounded tabs, colorful gradient backgrounds, and adaptive color schemes.

Why it matters now: Nova will replace Proton, Mozilla's current design system, with an interface that adapts to system color schemes automatically. Users who switch between light and dark modes will see the browser UI adjust its appearance without manual configuration, reducing the need to dig into settings. For Firefox users who toggle between modes throughout the day, this change could streamline their workflow.

According to Hentschel, development of the new design is still in its early stages, and the mockups shown are not official—they provide a general preview of what future Firefox may look like rather than final specifications.

What's changing: The design includes noticeably rounded tabs, address bar, and top navigation panel. The current monochrome surfaces will give way to colorful gradients reminiscent of Google's Material You design language. Based on the mockups, the interface will adapt its appearance depending on the selected color scheme.

Between the lines: The visual approach echoes Google's Material You, an adaptive color system that already influences Firefox for Android's recent interface updates. This alignment may signal tighter operating system integration and could create a more consistent experience for users who switch between desktop and mobile versions of the browser.

What's next: Mozilla has not announced a timeline for when the new design will roll out to all users. Because development remains in early stages, both the final appearance and release schedule remain uncertain.