4 best Cluster alternatives in 2021

Cluster is a bookmark manager with the following features: dark mode, tab management, drag and drop, importing/exporting, keyboard shortcuts.

Here are some great alternatives.

Workona is a way to manage your tabs and create documents from apps that you use online. It has a lot of apps that it connects with and allows you to organize them all in one place.
Organize your links in columns and boards similar to Trello. Allows you to save many tabs at once. Saves your links locally and not in the cloud.
Freeze tab is an easy way to manage your sessions by letting you save all your current tabs at once.
Hitabs allows you to organize tabs for teams and supports drag and drop.