StudyGate

StudyGate flips YouTube's default, nothing plays unless it belongs to a playlist you've explicitly whitelisted. No snooze timer. No "watch anyway" button. No fifteen-minute daily budget that resets your willpower along with the clock. If a video isn't on your list, it's blocked — full stop — until you add its playlist deliberately, in the extension's settings. How whitelisting works Add a course playlist, a lecture series, or a channel's upload playlist, and StudyGate indexes every video in it. Those videos then play normally whether you open them from the playlist or find them on their own, anywhere else on YouTube. Locked down by default, everywhere it matters • Every video and Short outside your whitelist — hard blocked, no exceptions • Shorts blocked entirely, since the format has no playlists to whitelist in the first place • Subscriptions tab — optional full block, for when even your subscribed channels are too easy to fall into • Home feed replaced with a message you write yourself, plus an editable checklist of things to do instead • "Up next" sidebar, endscreen suggestions, and pause overlays hidden on every watch page • YouTube's miniplayer can't be used to sneak a blocked video past you by popping it out after you navigate away Built to actually hold Going back from a blocked video doesn't let it keep playing quietly in the corner. Clicking through several blocked videos in a row doesn't leave a stale title on screen. The block screen shows you exactly what got blocked and why, with a rotating dose of "get back to it" via a small emoji and a line that changes every time. Zero data collection Everything — your whitelist, your settings, your checklist — lives in your browser's local storage. No account, no server, no analytics, no tracking. StudyGate never talks to anything except youtube.com, and only to check what's on your whitelist.