docs(config): note that hot-reloaded URL restrictions keep open targets attached (#3314)

Document on --blockedUrlPattern, --allowedUrlPattern, and
docs/configuration.md that targets already open on a newly disallowed
URL remain attached when patterns are updated via --watchConfig.

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docs/configuration.md

@@ -122,11 +122,11 @@ The Chrome DevTools MCP server supports the following configuration option:
   - **Default:** `false`
 
 - **`--blockedUrlPattern`/ `--blocked-url-pattern`**
-  Restricts browser's network access by blocking specified URL patterns (uses https://urlpattern.spec.whatwg.org/). Silently detaches from targets with blocked URLs upon connection, and blocks runtime requests (including navigations and subresources). Accepts an array of patterns. A pattern that uses a regexp group, a named group (`:name`), or a partial IPv4 wildcard (for example `(127\.\d+\.\d+\.\d+)`, `*://127.0.0.1::port/*`, or `*://127.0.0.*/*`) is rejected, because it is not enforced on redirects or subresources; use an exact value or a `*` wildcard instead. Patterns follow URL Pattern defaults: an omitted port matches only the scheme's default port (for example, `https://internal.corp/*` does not match `https://internal.corp:8443/`; use `https://internal.corp:*/*` to match any port), and the hostname must match exactly (a trailing-dot host such as `internal.corp.` is a different hostname).
+  Restricts browser's network access by blocking specified URL patterns (uses https://urlpattern.spec.whatwg.org/). Silently detaches from targets with blocked URLs upon connection, and blocks runtime requests (including navigations and subresources); targets already open when patterns are updated via --watchConfig remain attached. Accepts an array of patterns. A pattern that uses a regexp group, a named group (`:name`), or a partial IPv4 wildcard (for example `(127\.\d+\.\d+\.\d+)`, `*://127.0.0.1::port/*`, or `*://127.0.0.*/*`) is rejected, because it is not enforced on redirects or subresources; use an exact value or a `*` wildcard instead. Patterns follow URL Pattern defaults: an omitted port matches only the scheme's default port (for example, `https://internal.corp/*` does not match `https://internal.corp:8443/`; use `https://internal.corp:*/*` to match any port), and the hostname must match exactly (a trailing-dot host such as `internal.corp.` is a different hostname).
   - **Type:** array
 
 - **`--allowedUrlPattern`/ `--allowed-url-pattern`**
-  Restricts browser's network access by allowing only specified URL patterns (uses https://urlpattern.spec.whatwg.org/). Requires Chrome 149+. Silently detaches from targets with unallowed URLs upon connection, and blocks runtime requests (including navigations and subresources). Accepts an array of patterns. A pattern that uses a regexp group, a named group (`:name`), or a partial IPv4 wildcard (for example `(127\.\d+\.\d+\.\d+)`, `*://127.0.0.1::port/*`, or `*://127.0.0.*/*`) is rejected, because it is not enforced on redirects or subresources; use an exact value or a `*` wildcard instead. Patterns follow URL Pattern defaults: an omitted port matches only the scheme's default port (for example, `https://internal.corp/*` does not match `https://internal.corp:8443/`; use `https://internal.corp:*/*` to match any port), and the hostname must match exactly (a trailing-dot host such as `internal.corp.` is a different hostname).
+  Restricts browser's network access by allowing only specified URL patterns (uses https://urlpattern.spec.whatwg.org/). Requires Chrome 149+. Silently detaches from targets with unallowed URLs upon connection, and blocks runtime requests (including navigations and subresources); targets already open when patterns are updated via --watchConfig remain attached. Accepts an array of patterns. A pattern that uses a regexp group, a named group (`:name`), or a partial IPv4 wildcard (for example `(127\.\d+\.\d+\.\d+)`, `*://127.0.0.1::port/*`, or `*://127.0.0.*/*`) is rejected, because it is not enforced on redirects or subresources; use an exact value or a `*` wildcard instead. Patterns follow URL Pattern defaults: an omitted port matches only the scheme's default port (for example, `https://internal.corp/*` does not match `https://internal.corp:8443/`; use `https://internal.corp:*/*` to match any port), and the hostname must match exactly (a trailing-dot host such as `internal.corp.` is a different hostname).
   - **Type:** array
 
 - **`--screenshotFormat`/ `--screenshot-format`**
@@ -316,10 +316,12 @@ the error to stderr and keeps the previous configuration.
 
 Tool categories (except `categoryExtensions`), network URL restrictions
 (`blockedUrlPattern`, `allowedUrlPattern`), and tool-specific options apply
-immediately. Options that launch or connect to the browser, such as `headless`,
-`channel`, `viewport`, or `categoryExtensions`, only apply after restarting
-chrome-devtools-mcp. The server logs a message to stderr when a change requires
-a restart.
+immediately. When `blockedUrlPattern` or `allowedUrlPattern` is updated on the
+fly, future requests and navigations are restricted, but targets already open on
+a newly disallowed URL remain attached. Options that launch or connect to the
+browser, such as `headless`, `channel`, `viewport`, or `categoryExtensions`,
+only apply after restarting chrome-devtools-mcp. The server logs a message to
+stderr when a change requires a restart.
 
 ### Locking down the configuration file from agent access
 

src/config/puppeteer-options.ts

@@ -67,7 +67,7 @@ export const puppeteerOptions: PuppeteerOptions = {
     string: true,
     reloadable: true,
     describe:
-      "Restricts browser's network access by blocking specified URL patterns (uses https://urlpattern.spec.whatwg.org/). Silently detaches from targets with blocked URLs upon connection, and blocks runtime requests (including navigations and subresources). Accepts an array of patterns. A pattern that uses a regexp group, a named group (`:name`), or a partial IPv4 wildcard (for example `(127\\.\\d+\\.\\d+\\.\\d+)`, `*://127.0.0.1::port/*`, or `*://127.0.0.*/*`) is rejected, because it is not enforced on redirects or subresources; use an exact value or a `*` wildcard instead. Patterns follow URL Pattern defaults: an omitted port matches only the scheme's default port (for example, `https://internal.corp/*` does not match `https://internal.corp:8443/`; use `https://internal.corp:*/*` to match any port), and the hostname must match exactly (a trailing-dot host such as `internal.corp.` is a different hostname).",
+      "Restricts browser's network access by blocking specified URL patterns (uses https://urlpattern.spec.whatwg.org/). Silently detaches from targets with blocked URLs upon connection, and blocks runtime requests (including navigations and subresources); targets already open when patterns are updated via --watchConfig remain attached. Accepts an array of patterns. A pattern that uses a regexp group, a named group (`:name`), or a partial IPv4 wildcard (for example `(127\\.\\d+\\.\\d+\\.\\d+)`, `*://127.0.0.1::port/*`, or `*://127.0.0.*/*`) is rejected, because it is not enforced on redirects or subresources; use an exact value or a `*` wildcard instead. Patterns follow URL Pattern defaults: an omitted port matches only the scheme's default port (for example, `https://internal.corp/*` does not match `https://internal.corp:8443/`; use `https://internal.corp:*/*` to match any port), and the hostname must match exactly (a trailing-dot host such as `internal.corp.` is a different hostname).",
     coerce: (arg: string[] | undefined): string[] | undefined => {
       if (arg === undefined || arg.length === 0) {
         return undefined;
@@ -81,7 +81,7 @@ export const puppeteerOptions: PuppeteerOptions = {
     string: true,
     reloadable: true,
     describe:
-      "Restricts browser's network access by allowing only specified URL patterns (uses https://urlpattern.spec.whatwg.org/). Requires Chrome 149+. Silently detaches from targets with unallowed URLs upon connection, and blocks runtime requests (including navigations and subresources). Accepts an array of patterns. A pattern that uses a regexp group, a named group (`:name`), or a partial IPv4 wildcard (for example `(127\\.\\d+\\.\\d+\\.\\d+)`, `*://127.0.0.1::port/*`, or `*://127.0.0.*/*`) is rejected, because it is not enforced on redirects or subresources; use an exact value or a `*` wildcard instead. Patterns follow URL Pattern defaults: an omitted port matches only the scheme's default port (for example, `https://internal.corp/*` does not match `https://internal.corp:8443/`; use `https://internal.corp:*/*` to match any port), and the hostname must match exactly (a trailing-dot host such as `internal.corp.` is a different hostname).",
+      "Restricts browser's network access by allowing only specified URL patterns (uses https://urlpattern.spec.whatwg.org/). Requires Chrome 149+. Silently detaches from targets with unallowed URLs upon connection, and blocks runtime requests (including navigations and subresources); targets already open when patterns are updated via --watchConfig remain attached. Accepts an array of patterns. A pattern that uses a regexp group, a named group (`:name`), or a partial IPv4 wildcard (for example `(127\\.\\d+\\.\\d+\\.\\d+)`, `*://127.0.0.1::port/*`, or `*://127.0.0.*/*`) is rejected, because it is not enforced on redirects or subresources; use an exact value or a `*` wildcard instead. Patterns follow URL Pattern defaults: an omitted port matches only the scheme's default port (for example, `https://internal.corp/*` does not match `https://internal.corp:8443/`; use `https://internal.corp:*/*` to match any port), and the hostname must match exactly (a trailing-dot host such as `internal.corp.` is a different hostname).",
     coerce: (arg: string[] | undefined): string[] | undefined => {
       if (arg === undefined) {
         return undefined;