An unofficial version of the Vivaldi browser in flatpak format, prepared by one of the company’s employees, has been published on Flathub. The unofficial status of the package is explained by various factors, in particular, there is still no complete confidence that the Chromium sandbox will be sufficiently safe when running in the Flatpak environment. If no special problems arise in the future, the package will be transferred to official status.
The appearance of Vivaldi assemblies in the Flatpak format allows you to expand the capabilities of installing the browser in various distributions without the need to prepare specialized packages. Also, despite the unofficial status for now, Vivaldi developers will process error messages for this version along with all others in order to promptly make the necessary corrections.
Source: opennet.ru