Chrome Safety Check auto-revokes idle clipboard permissions in Canary

Google’s Chrome is quietly treating copy-and-paste as a first‑class privacy risk: Canary builds now show Safety Check automatically removing clipboard permissions from sites you haven’t visited recently, surface a clear “Removed permissions for [x] sites” notice in the menu, and give users a one‑click path to restore access — signaling that clipboard access is no longer a casual, forever‑granted capability. (blog.google)

Background​

Chrome’s Safety Check has evolved from a static checklist into a proactive housekeeping engine that runs in the background and intervenes when it detects risky or unused permissions. The feature now automatically removes permissions from sites you don’t visit anymore, and informs you of the action in the browser UI so you can review and, if needed, restore them. This behavior — now visible in Canary — is part of Google’s broader update to Safety Check that introduced one‑time permissions, improved notification controls, and automated cleanup for stale site grants. (blog.google, chromium.googlesource.com)
Under the hood, the Chromium project exposes a feature called the “Unused Site Permissions” module. The codebase includes feature flags, time thresholds for treating a site as “unused,” and the plumbing that stores revoked permissions and later allows them to be re‑granted from the Safety Check UI. Chromium strings and settings show the exact UX language used in the UI: “To protect your data, permissions were removed from a site you haven’t visited recently” and an option to “Allow again.” That infrastructure is what enables the clipboard‑specific message testers are now seeing in Canary builds. (chromium.googlesource.com)

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What changed in Canary (what you’re actually seeing)​

• Safety Check will run in the background (or when you open it) and revoke permissions for unused sites. The menu can show a short toast such as “Removed permissions for [x] sites,” which opens Safety Check and lists the affected origins. (blog.google, chromium.googlesource.com)
• Canary’s Safety Check UI explicitly lists the clipboard as one of the permission types that can be revoked from idle sites; the pop‑up and Safety Check entries include an Allow again button so you can re‑enable clipboard access quickly if you trust the site. This reversible flow encourages a deliberate decision rather than silent, permanent revocation.
• Settings remain available for manual control: you can manage clipboard permissions directly at chrome://settings/content/clipboard (Chrome’s content settings dialog includes categories like “Ask before allowing sites to read the clipboard”). The browser’s site‑settings infrastructure supports granular control for clipboard read/write behavior. (chromium.googlesource.com)

These changes are rolling out behind Canary flags and the Safety Check module of Chromium, so wording and exact behavior may change as the experiment matures and moves through Dev/Beta channels.

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Why clipboard access matters (technical & practical risks)​

Clipboard contents are frequently more sensitive than users realize. People copy and paste:

• Passwords and one‑time codes, often when a password generator or manager fills a form.
• Credit card or bank details during payment workflows.
• Cryptocurrency addresses, which are long and error‑prone — a common target for clipboard‑overwrite attacks.
• Confidential snippets from documents, internal URLs, tokens, or personally identifiable information.

Because the clipboard is a global, cross‑process buffer, any web page or extension that can read the clipboard (with appropriate permission) can access that data. In the past, a Chrome bug removed required user gestures for clipboard writes and created scenarios where sites could overwrite the clipboard silently — a vector used in real‑world attacks and demonstrated by security researchers. Revoking clipboard access for dormant origins reduces the window of exposure and stops long‑forgotten permissions from becoming an ongoing risk. (bleepingcomputer.com)

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How the auto‑revocation flow actually works (implementation details)​

• Chromium keeps track of site permissions and usage metadata inside the HostContentSettingsMap and related services. When the “Unused Site Permissions” feature is enabled, the browser will periodically consider whether an origin has been visited recently. If the origin is classified as “unused” beyond an internal threshold, Safety Check may revoke the permissions stored for that origin (camera, mic, location, clipboard, etc.). The code includes configurable parameters for thresholds and cleanup windows. (chromium.googlesource.com)
• Those revoked permissions are surfaced in the Safety Check UI under a module that lists revoked unused‑site permissions. Accessibility and UX strings in Chromium confirm the user‑facing labels — and the UI exposes “Allow again” actions that call back into the permissions service to regrant the previously revoked permissions. This is a deliberate two‑step model: auto‑protect now, let the user decide later. (chromium.googlesource.com)
• When Chrome revokes a permission, the browser also shows a toast or menu prompt (“Permissions removed for X site(s)”) that brings you to Safety Check. From there you can review which permissions were removed, and optionally click “Allow again” to restore clipboard access with one click. This UX nudges users to think before granting persistent access again. (blog.google, chromium.googlesource.com)

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Benefits for everyday users and enterprises​

• Smaller attack surface: Permissions that linger after a one‑off interaction are a persistent risk. Auto‑revocation reduces the timeframe an origin can read your clipboard without fresh user intent. (chromium.googlesource.com)
• Better default privacy posture: Most users either don’t know to revoke or forget about site permissions. Safety Check brings these stale grants into a single reviewable place and handles cleanup automatically. (blog.google)
• Easy recovery: The “Allow again” button prevents accidental breakage: trusted sites can be restored quickly without digging into site settings. (chromium.googlesource.com)
• Enterprise controls and auditability: Chromium’s feature flags and service hooks (feature params for revocation thresholds and cleanup) make it feasible for admins to tune behavior; enterprises can test and delay adoption until they’ve validated interactions with DLP and other tooling. The underlying feature definitions expose points where admins can expect manageability hooks to eventually appear. (chromium.googlesource.com)

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Important limitations and potential downsides​

• Workflow interruption for legitimate sites and apps. Sites that require ongoing clipboard access — for example, web‑based password managers, clipboard‑syncing productivity apps, virtual labs or developer tools — may lose functionality when their permissions are auto‑revoked. Users who rely on continuous clipboard access might see frequent prompts to re‑allow, which can be annoying without good discoverability of why the permission was removed. The “Allow again” button helps but does not eliminate friction. (chromium.googlesource.com)
• Notification fatigue. If Safety Check revokes permissions for a long list of sites, the UI could generate multiple toasts or warnings, causing users to reflexively ignore or dismiss them. Balancing how and when the browser surfaces these actions will be key to adoption. (blog.google)
• Edge cases with extensions and PWAs. Browser extensions and progressive web apps can also request clipboard access. The revocation model targets site grants stored in content settings; extension behavior and extension UIs can behave differently, which may complicate troubleshooting for users who suddenly find a feature “broken.” Extension authors may need to rework flows to request ephemeral or on‑demand permissions. (developer.chrome.com, chromium.googlesource.com)
• Enterprise DLP integration is not automatic. Until DLP vendors and enterprise admin tooling explicitly account for the Safety Check revocation calendar, organizations must treat the feature experimentally and validate interactions with their DLP, MDM/Intune, and auditing systems. Chromium’s feature parameters suggest admin controls are possible, but organizations should request explicit policy hooks before enabling across managed fleets. (chromium.googlesource.com)

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Real‑world examples and why this is timely​

• Clipboard overwrite attacks (where a malicious page silently writes a bad wallet address or payment string to the clipboard) are a documented real‑world risk. Chrome’s decision to treat clipboard as a revocable permission recognizes that the clipboard is a high‑risk channel for exfiltration and fraud. The security community has warned about clipboard abuse for years, and browser vendors have periodically tightened rules (for instance, requiring gestures for writes or making reads gated by explicit user intent). Automatic revocation of stale grants is a practical, layered defense. (bleepingcomputer.com)
• Users have long relied on clipboard persistence as a convenience, but convenience without time‑bounded intent is the problem. Apple’s ecosystems and some third‑party tools offer controlled cross‑device clipboard sync (with varying degrees of encryption and retention guarantees), but the web is a different security model. Browsers must now reconcile user convenience with the reality that clipboard contents are frequently sensitive. Chrome’s Safety Check move is one way to do that at scale. (chromium.googlesource.com)

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Practical advice for Windows users​

• To review revoked permissions and re‑allow clipboard access, open Chrome’s menu and follow the “Removed permissions for X sites” notification to Safety Check, or go directly to chrome://settings/safetyCheck and review the “Unused site permissions” module. If you prefer manual control, visit chrome://settings/content/clipboard to manage per‑site clipboard rules. (blog.google, chromium.googlesource.com)
• If a legitimate site breaks after a revocation (for instance, a web‑based password vault), choose “Allow again” from Safety Check or add a site allowance manually in site settings. For critical workflows, consider whitelisting highly trusted domains or using an alternate workflow (native password managers or local clipboard utilities) that doesn’t rely on persistent web permissions. (chromium.googlesource.com)
• IT teams should pilot the feature in a test group before broad rollouts. Validate interactions with password managers, single‑sign‑on pages, and internal web apps that expect long‑lived permissions. Also confirm DLP telemetry and audit logs remain functional after revocation events. Chromium’s feature flags offer testing knobs for revocation timing that can help with staged pilots. (chromium.googlesource.com)

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How browser vendors landed here — policy and engineering signals​

Chromium’s repository shows deliberate engineering work to support auto‑revocation: feature flags, parameters to tune time thresholds and cleanup intervals, and explicit UI handlers to regrant permissions. These are signs the team is designing the feature as policy‑driven and tunable rather than a hard, irreversible block. Expect the UX and thresholds to be refined as telemetry from Canary and Dev channels arrives. (chromium.googlesource.com)
Google’s official blog and product announcements frame Safety Check as a broader privacy and security update (one‑time permissions, abusive notification detection, and extension checks). That public messaging lines up with the technical changes in Chromium — a coordinated push to make permission hygiene automatic while leaving control in the hands of users. (blog.google, thehackernews.com)

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What to watch next​

• Will Google expose enterprise policies (Intune/GPO) to control the revocation thresholds and exceptions? The Chromium feature design suggests this is feasible and likely — but enterprises should demand explicit controls and documentation before rolling the change out widely. (chromium.googlesource.com)
• How will other Chromium‑based browsers adopt or diverge from this model? Brave, Edge, Opera, and others may implement similar hygiene or choose different defaults; downstream UX and admin hooks will vary. The change will be most meaningful if it becomes a cross‑browser standard. (github.com)
• Will Google refine the “Allow again” UX to avoid repeated friction for legitimate use cases? Expect tweaks: whitelist affordances, less intrusive banners for power users, or an “always allow for this origin on this device” option to reduce repeated prompts.

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Bottom line​

Chrome’s Safety Check revocation for clipboard permissions represents a pragmatic, engineering‑backed shift toward time‑bounded privacy. By treating clipboard access as a high‑risk permission and making automatic revocation visible and reversible, Chrome moves the default from “permanent grant” toward “granted only while needed.” That reduces exposure to clipboard overwrite attacks and stale‑permission leaks, but it introduces friction for some legitimate workflows and raises questions about enterprise manageability and extension interactions.
Users should welcome the protective default, while power users and IT teams should plan short pilots to understand and tune how the change interacts with password managers, clipboard sync tools, and internal web applications. For now, Chrome gives you both an automated defender and an easy recovery button: a sensible compromise between safety and usability — provided the browser gets the thresholds, messaging, and manageability right as the feature leaves Canary and moves toward stable channels. (blog.google, chromium.googlesource.com)

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Source: Windows Report Chrome Is Now Watching Your Clipboard Permissions — Here’s What That Means