RelaxedReader is your typical reading list/bookmarking tool, with a few important differences:

You can store a maximum of 10 articles. If you add more, the oldest will get pushed out (FIFO).
Items automatically expire after 30 days.
No notifications, badges, unread counts or anything else that prompts anxiety and/or FOMO.
No tracking, third party servers or API calls. All data is stored in extension storage.
Uses storage.sync, so the reading list is synced across all instances of the browser that the user is logged into, across different devices.