diff --git a/testing/talos/talos/tests/devtools/addon/content/damp-tests.js b/testing/talos/talos/tests/devtools/addon/content/damp-tests.js
index 9c67a51cd4cf..87a91893521e 100644
--- a/testing/talos/talos/tests/devtools/addon/content/damp-tests.js
+++ b/testing/talos/talos/tests/devtools/addon/content/damp-tests.js
@@ -20,10 +20,33 @@
  */
 
 module.exports = [
+  // The first cold-open test is *colder* than the other cold-open tests, it will also
+  // assess the impact of loading shared DevTools modules for the first time.
+  // This test will assert the impact of base loader/Loader.jsm modules loading,
+  // typically gDevtools/gDevToolsBrowser/Framework modules, while the others will mostly
+  // track panel-specific modules (Browser loader, but not only).
   {
     name: "inspector.cold-open",
     path: "inspector/cold-open.js",
-    description: "Measure first open toolbox on inspector panel",
+    description: "Measure first open toolbox on inspector panel (incl. shared modules)",
+    cold: true,
+  },
+  {
+    name: "debugger.cold-open",
+    path: "debugger/cold-open.js",
+    description: "Measure first open toolbox on debugger panel",
+    cold: true,
+  },
+  {
+    name: "webconsole.cold-open",
+    path: "webconsole/cold-open.js",
+    description: "Measure first open toolbox on webconsole panel",
+    cold: true,
+  },
+  {
+    name: "netmonitor.cold-open",
+    path: "netmonitor/cold-open.js",
+    description: "Measure first open toolbox on netmonitor panel",
     cold: true,
   },
   // Run all tests against "simple" document
diff --git a/testing/talos/talos/tests/devtools/addon/content/tests/debugger/cold-open.js b/testing/talos/talos/tests/devtools/addon/content/tests/debugger/cold-open.js
new file mode 100644
index 000000000000..a1d0b2ab2514
--- /dev/null
+++ b/testing/talos/talos/tests/devtools/addon/content/tests/debugger/cold-open.js
@@ -0,0 +1,22 @@
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+"use strict";
+
+const { closeToolbox, testSetup, testTeardown, SIMPLE_URL } = require("../head");
+const { openDebuggerAndLog } = require("./debugger-helpers");
+
+const EXPECTED = {
+  sources: 1,
+  file: "simple.html",
+  sourceURL: SIMPLE_URL,
+  text: "This is a simple page",
+};
+
+module.exports = async function() {
+  await testSetup(SIMPLE_URL);
+  await openDebuggerAndLog("cold", EXPECTED);
+  await closeToolbox();
+  await testTeardown();
+};
diff --git a/testing/talos/talos/tests/devtools/addon/content/tests/netmonitor/cold-open.js b/testing/talos/talos/tests/devtools/addon/content/tests/netmonitor/cold-open.js
new file mode 100644
index 000000000000..78c75bc027e0
--- /dev/null
+++ b/testing/talos/talos/tests/devtools/addon/content/tests/netmonitor/cold-open.js
@@ -0,0 +1,15 @@
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+"use strict";
+
+const { openToolboxAndLog, closeToolbox, testSetup,
+        testTeardown, SIMPLE_URL } = require("../head");
+
+module.exports = async function() {
+  await testSetup(SIMPLE_URL);
+  await openToolboxAndLog("cold.netmonitor", "netmonitor");
+  await closeToolbox();
+  await testTeardown();
+};
diff --git a/testing/talos/talos/tests/devtools/addon/content/tests/webconsole/cold-open.js b/testing/talos/talos/tests/devtools/addon/content/tests/webconsole/cold-open.js
new file mode 100644
index 000000000000..edc6551b0d70
--- /dev/null
+++ b/testing/talos/talos/tests/devtools/addon/content/tests/webconsole/cold-open.js
@@ -0,0 +1,15 @@
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+"use strict";
+
+const { openToolboxAndLog, closeToolbox, testSetup,
+        testTeardown, SIMPLE_URL } = require("../head");
+
+module.exports = async function() {
+  await testSetup(SIMPLE_URL);
+  await openToolboxAndLog("cold.webconsole", "webconsole");
+  await closeToolbox();
+  await testTeardown();
+};