CUSTODIAN
About
An extension with one job.
Custodian keeps an eye on your open tabs. When you close the last tab for a site, it waits a few seconds in case that was an accident, then clears that site's cookies, storage, and cache, and resets whatever permissions it had.
Why it exists
Most browser cleanup tools work on a timer or wait for you to click a button, which means either you lose things you're still using or you have to remember to do it yourself. Neither matches how people actually browse: you open a site, you use it, and at some point you're done with it, usually marked by closing its tabs. Custodian is built around that moment specifically, because it's the one point where "done with this site" is actually knowable without guessing.
What it isn't
It's not a manual "clear cache" button, and it's not a privacy dashboard that asks you to review and approve every action. It's automatic, per-site, and triggered by closing a site's last tab. The only thing it asks of you, by default, is a five-second window to change your mind.
No account, nothing sent anywhere
There's no account to sign into and nothing sent off your machine. Custodian doesn't know who you are because it never asks, and it has no server to report back to even if it wanted to. Everything it knows, your whitelist, your greylist, your settings, your activity log, lives in your browser's local storage and stays there. Uninstalling the extension removes all of it.
This isn't a workaround or a limitation we're stuck with. It's the design: a tool that manages what a site can keep about you shouldn't need to keep anything about you itself.
Who it's for
People who close a lot of tabs and would rather not think about what those sites are still holding onto. It's equally useful for a one-off login on a site you'll never revisit and for the sites you use daily but don't want lingering in the background between sessions.