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+# WebExtensions
+
+## Manifest v3
+
+## declarativeNetRequest
+
+Instead of procedurally blocking or modifying requests and responses, requires developers to implement a "rules" DSL on how requests should be blocked by the browser:
+Consists of four properties, one of which is optional:
+
+* `id`
+* `priority` (optional). If left off, `priority`=1
+* `condition`, an object containing predicate(s) the browser will evaluate.
+* `action`, the response to take if the condition yields true, an object where the `type` property is either `block` or `modifyHeaders`.
+
+### [`updateStaticRules`](https://developer.chrome.com/docs/extensions/reference/api/declarativeNetRequest#method-updateStaticRules)
+
+Supposedly implemented in Chrome 111 (associated GitHub ticket), with [chromium tests here](https://chromium.googlesource.com/chromium/src/+/86cf9e194ae801b3bfde08c253a7a12dae6b0cb7/chrome/test/data/extensions/api_test/declarative_net_request/update_static_rules/background.js).
+However, doesn't actually appear to work in the real-world—static rules that are disabled via this method call continue to be registered with the `declarativeNetRequest` API and continue work.
+Programmatically though, the API seems to function correctly to the point where the unit tests implemented in Chromium obviously pass.
+
+Not implemented in Safari ([WebKit ticket](https://bugs.webkit.org/show_bug.cgi?id=261039)) or Firefox.
+
+### `updateEnabledRulesets`
+
+A workaround is instead of updating rules, just have one rule per ruleset and use the actually functional (in Chrome) at least `updateEnabledRulesets`.