From f25f3df2abfaad084fdd69e4c729ed64e159b20a Mon Sep 17 00:00:00 2001
From: Nikolay Vitkov <34244704+Lightning00Blade@users.noreply.github.com>
Date: Thu, 22 Oct 2026 12:12:48 +0000
Subject: [PATCH] fix(network): reset page network emulation before applying
 URL restrictions (#3312)
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Call emulateNetworkConditions(null) in McpPage.clearNetworkConditions()
and await it before browser.restrictNetwork() in
McpContext.syncNetworkRestrictions() so emulated offline/throttled state
(such as navigator.onLine) is cleared when URL restrictions are
hot-reloaded.

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---
 src/McpContext.ts        | 10 +++++-----
 src/McpPage.ts           |  3 ++-
 tests/McpContext.test.ts | 12 ++++++++++--
 tests/McpPage.test.ts    | 10 ++++++++--
 4 files changed, 25 insertions(+), 10 deletions(-)

diff --git a/src/McpContext.ts b/src/McpContext.ts
index 19103716..fa15ff67 100644
--- a/src/McpContext.ts
+++ b/src/McpContext.ts
@@ -251,17 +251,17 @@ export class McpContext implements Context, BrowserlessContext {
    */
   async syncNetworkRestrictions(): Promise<void> {
     const {blockedUrlPattern, allowedUrlPattern} = this.#config.resolved;
+    if (blockedUrlPattern || allowedUrlPattern) {
+      for (const mcpPage of this.#allMcpPages()) {
+        await mcpPage.clearNetworkConditions();
+      }
+    }
     if (this.#browser) {
       await this.#browser.restrictNetwork({
         blocklist: blockedUrlPattern,
         allowlist: allowedUrlPattern,
       });
     }
-    if (blockedUrlPattern || allowedUrlPattern) {
-      for (const mcpPage of this.#allMcpPages()) {
-        mcpPage.clearNetworkConditions();
-      }
-    }
   }
 
   /**
diff --git a/src/McpPage.ts b/src/McpPage.ts
index bb8ff94a..4d74d91d 100644
--- a/src/McpPage.ts
+++ b/src/McpPage.ts
@@ -1337,10 +1337,11 @@ export class McpPage implements ContextPage {
     }
   }
 
-  clearNetworkConditions(): void {
+  async clearNetworkConditions(): Promise<void> {
     if (!this.emulationSettings.networkConditions) {
       return;
     }
+    await this.#pptrPage?.emulateNetworkConditions(null);
     delete this.emulationSettings.networkConditions;
     this.updateTimeouts();
   }
diff --git a/tests/McpContext.test.ts b/tests/McpContext.test.ts
index 5ddd2b78..9ed5c124 100644
--- a/tests/McpContext.test.ts
+++ b/tests/McpContext.test.ts
@@ -1747,11 +1747,15 @@ describe('McpContext', () => {
       await updateConfig(config, context, {
         blockedUrlPattern: ['https://blocked.example.com/*'],
       });
+      sinon.assert.calledOnceWithExactly(clearNetworkConditionsSpy);
       sinon.assert.calledOnceWithExactly(browser.restrictNetwork, {
         blocklist: ['https://blocked.example.com/*'],
         allowlist: undefined,
       });
-      sinon.assert.calledOnceWithExactly(clearNetworkConditionsSpy);
+      sinon.assert.callOrder(
+        clearNetworkConditionsSpy,
+        browser.restrictNetwork,
+      );
 
       browser.restrictNetwork.resetHistory();
       clearNetworkConditionsSpy.resetHistory();
@@ -1765,11 +1769,15 @@ describe('McpContext', () => {
         blockedUrlPattern: undefined,
         allowedUrlPattern: ['https://allowed.example.com/*'],
       });
+      sinon.assert.calledOnceWithExactly(clearNetworkConditionsSpy);
       sinon.assert.calledOnceWithExactly(browser.restrictNetwork, {
         blocklist: undefined,
         allowlist: ['https://allowed.example.com/*'],
       });
-      sinon.assert.calledOnceWithExactly(clearNetworkConditionsSpy);
+      sinon.assert.callOrder(
+        clearNetworkConditionsSpy,
+        browser.restrictNetwork,
+      );
 
       browser.restrictNetwork.resetHistory();
       clearNetworkConditionsSpy.resetHistory();
diff --git a/tests/McpPage.test.ts b/tests/McpPage.test.ts
index 4a6d8088..67867d82 100644
--- a/tests/McpPage.test.ts
+++ b/tests/McpPage.test.ts
@@ -1015,6 +1015,7 @@ describe('McpPage', () => {
         networkConditions: 'Slow 3G',
         cpuThrottlingRate: 2,
       });
+      pptrPage.emulateNetworkConditions.resetHistory();
       pptrPage.setDefaultTimeout.resetHistory();
       pptrPage.setDefaultNavigationTimeout.resetHistory();
       config.commit(
@@ -1023,10 +1024,14 @@ describe('McpPage', () => {
         }),
       );
 
-      mcpPage.clearNetworkConditions();
+      await mcpPage.clearNetworkConditions();
 
       assert.strictEqual(mcpPage.networkConditions, null);
       assert.strictEqual(mcpPage.cpuThrottlingRate, 2);
+      sinon.assert.calledOnceWithExactly(
+        pptrPage.emulateNetworkConditions,
+        null,
+      );
       sinon.assert.calledOnceWithExactly(pptrPage.setDefaultTimeout, 10_000);
       sinon.assert.calledOnceWithExactly(
         pptrPage.setDefaultNavigationTimeout,
@@ -1040,8 +1045,9 @@ describe('McpPage', () => {
       pptrPage.setDefaultTimeout.resetHistory();
       pptrPage.setDefaultNavigationTimeout.resetHistory();
 
-      mcpPage.clearNetworkConditions();
+      await mcpPage.clearNetworkConditions();
 
+      sinon.assert.notCalled(pptrPage.emulateNetworkConditions);
       sinon.assert.notCalled(pptrPage.setDefaultTimeout);
       sinon.assert.notCalled(pptrPage.setDefaultNavigationTimeout);
     });