Reading with monitor for a long time is unavoidable to people and it strains your eyes.
It's necessary to rest your eyes every 50 minutes you spent with monitor.
And this extension notices you on a timely basis w/ a decent user interface.

Why this extension require Access your data for all websites?
Since you are able to set your own notification sound, which may located on any server. I thought asking this permission is required. I will minimize this once I knew there is better solution. You may concerned about security. I can guarantee that the program is build directly from source, and the source code is on GitHub, I didn't abuse with this permission.

Install

• License: Mozilla Public License 2.0
• Weekly downloads: 7
• Average daily users: 353
• Rating: 4.6923/5 of 39 ratings
• Created: 2017-02-19 11:50:18
• Last updated: 2021-05-03 14:50:29
• Homepage: https://github.com/artyomliou/eyes-alarm
• Support site and email
• Orig: https://addons.mozilla.org/en-US/firefox/addon/eyes-alarm/
• API: {548c04e1-8687-42d1-8b1c-032dc42be5b7}