Why website blockers "stop working" (and how to fix it)

A website blocker rarely fails all at once — it fails quietly, one workaround at a time: a different browser, a private window, a VPN, or the extension being removed. None of those is a mystery once named, and picking a blocker that surfaces these gaps instead of hiding them is what keeps blocking working past the first week.

Why does a website blocker that worked yesterday stop working today?

Most reports of a blocker "not working" trace back to one of a handful of ordinary changes, not a defect. A child switches to a browser the blocker was never installed in — Chrome is not the only option, and Firefox, Edge, or Brave each start with a clean slate. A new Chrome profile or a guest window can do the same thing inside Chrome itself.

Incognito mode is another common cause, though what it actually changes is narrower than it seems: it stops the browser from saving local history, cookies, and site data, but it does not block content, stop trackers, or hide activity from the network the device is connected to. Whether a blocker keeps working in an incognito window depends entirely on whether the extension was allowed to run there — a setting Chrome asks about at install time and one worth checking rather than assuming.

Do most parental-control tools actually block what they claim to?

Not automatically, even among established vendors. AV-Comparatives runs an annual certification test for parental-control products, requiring a block rate of at least 95% against a set of pornographic test sites, zero false positives across 200 child-friendly sites, and no severe unresolved bugs. In the 2025 round, five vendors submitted products for testing and only two met all three requirements; the one reviewed in detail, Kaspersky Safe Kids, blocked 96.8% of the test set with zero false positives (AV-Comparatives, 2025).

That gap — three of five vendors falling short of a 95% bar most parents would assume is a baseline — is a useful reminder that "blocks websites" is not a single, uniform feature. It is worth checking whether a vendor publishes independent test results at all, rather than only its own marketing numbers.

How do children actually get a website blocker to fail?

Beyond switching browsers, three tactics account for most real-world workarounds. A VPN reroutes traffic so a filter checking network-level signals may no longer see what it expects, even if the destination address has not changed from the browser's point of view. Uninstalling or disabling the extension outright is the most direct route, and on an unmanaged personal device there is often nothing stopping it. And a device that goes offline, or stops checking in with whatever service enforces the rules, can quietly stop being covered at all — not through anyone bypassing anything, just through a gap nobody noticed.

A November 2025 survey of 2,018 children aged 8–17 in the UK, run by Opinium for Childnet and Nominet, found that 21% had used a VPN, rising from 15% of 8–10-year-olds to 27% of 15–17-year-olds. Of those, 16% named getting around parental controls as a reason for using one, and the same share cited getting around school monitoring (Childnet/Nominet, November 2025). That does not mean every VPN use is an attempt to defeat a blocker — privacy and streaming access were both cited more often as the main reason — but it does mean VPN use is common enough that a blocker with no answer for it is missing a real-world case, not an edge case.

What should a parent look for in a blocker that keeps holding up?

A blocker that survives past the first week tends to share a few traits that have nothing to do with how strict its default block list is:

• It covers more than one browser profile, so a fresh Chrome profile or guest window is not automatically an exit.
• It flags when a device stops checking in, instead of assuming silence means everything is fine.
• Its rules are enforced from outside the browser tab itself, so closing or disabling one piece does not quietly disable the whole thing.
• It is honest about what it cannot do. A product that claims to be undetectable or unbypassable is making a promise that the AV-Comparatives results above suggest even well-established vendors cannot always keep — a specific, disclosed limit is more useful than a blanket claim.

Where does StudyLock fit into this?

StudyLock is built around the idea that a browser extension can, in fact, be removed — so instead of promising otherwise, it is designed to keep the last set of rules enforced even if a device loses its connection, and to surface when a child's Chrome has stopped checking in at all, so a parent notices a gap instead of assuming coverage that is not there. Focus schedules and blocked-site rules are set once from the parent dashboard and apply across the child's Chrome profile; see how StudyLock works for the setup steps, or go straight to getting started.

Reliability is only one half of choosing a blocker well. The other is knowing what the tool itself does with the access it needs to work, which is covered in are parental control extensions safe?