Raindrop.io - All your articles, photos, video & content from web & apps in one place.
Bookmark OS - Bookmark OS is like Mac or Windows optimized for bookmarks.
Linkman - Linkman Pro allows for managing large amount of URLs in its own database.
Pocket - When you find something you want to view later, put it in Pocket.
Diigo - Diigo is a powerful research tool and a knowledge-sharing community
Floccus - Sync your web data across browsers and devices via your Nextcloud!