Vivaldi browser already supports Tab Stacks. Tab Stacks are groups of browser tabs which will help you keep yourself organised while you browse. Until now, you have to create these Tab Stacks manually according to your needs. Today, the Vivaldi browser announced the release Vivaldi 2.3 update which brings auto-stacking of tabs. After enabling this setting, whenever you open a link from the active tab, it is automatically added to a Tab Stack. You can enable this feature in Settings > Tabs > New Tab Position > Select “As Tab Stack With Related Tabs”.
In this update, users can now enable frequently visited pages to be displayed in the Address field drop-down. Also, this update brings improvements to screenshot capture experience.
You can download this update from Vivaldi here.