Every site blocker makes you maintain a list of "bad" sites. That list never ends. Lockby flips the model. Pick the 1-3 domains you need for your current task, set a timer, and everything else disappears. Non-whitelisted tabs get killed before the page loads. No loopholes. Want to quit early? You have to type a full sentence and wait 5 seconds. It's a speed bump between impulse and action. Built for ADHD brains and chronic tab-openers Works on Chrome, Edge, Brave, and Arc.