NoProcrast от Prateek Ganguli

A browser extension that limits time spent on distracting websites, modeled on Hacker News's noprocrast feature.

Each blocked site gets a configurable visit window (maxvisit minutes). Once that window is used up, the tab redirects to a block page and stays blocked for a cooldown period (minaway minutes). A manual override is available but only resets the timer — it does not disable the system.