OnHand by Yegor Pelykh

Сreated for easy and convenient management of your favorite sites, which can be opened directly from a browser "new tab" page.

Neat and minimalistic. Uses material design.

Features:
- adding bookmarks in a simple way
- grouping bookmarks using tabs
- easy data management, loading and saving to a file, without clouds and accounts
- supports switching between light and dark theme (it depends on the theme color of the operating system)

Supported by almost all popular desktop browsers in the world (except Opera): Google Chrome, Firefox, Edge, Chromium etc.

This extension is guaranteed to always be free and open source.

The extension is multilingual. At the moment, only three languages are implemented and supported: English, Russian and Ukrainian.
Other languages can easily be added.
I would be grateful for your cooperation.