Ember — Strict Mode by Parth Batav

"Ember's Strict Mode is a companion to the Deep Work Timer in the main Ember app. When you start a focus session, Strict Mode optionally blocks distracting sites you've chosen (social media, video sites, etc.) for the duration of that session. You're always in control — you choose what's blocked, you can turn it off anytime, and it only activates alongside a session you've started yourself in the Ember app."