diff --git a/devtools/client/debugger/test/mochitest/browser.ini b/devtools/client/debugger/test/mochitest/browser.ini
index 55fa6b9bbc3b..34ad6aca950f 100644
--- a/devtools/client/debugger/test/mochitest/browser.ini
+++ b/devtools/client/debugger/test/mochitest/browser.ini
@@ -7,6 +7,7 @@ support-files =
   head.js
   helpers.js
   helpers/context.js
+  !/devtools/client/framework/test/helpers.js
   !/devtools/client/inspector/test/head.js
   !/devtools/client/inspector/test/shared-head.js
   !/devtools/client/shared/test/shared-head.js
@@ -176,3 +177,4 @@ skip-if = true #Bug 1456013, Bug 1559547, Bug 1571863
 [browser_dbg-gc-sources.js]
 [browser_dbg-watchpoints.js]
 skip-if = debug
+[browser_dbg-toolbox-unselected-pause.js]
diff --git a/devtools/client/debugger/test/mochitest/browser_dbg-toolbox-unselected-pause.js b/devtools/client/debugger/test/mochitest/browser_dbg-toolbox-unselected-pause.js
new file mode 100644
index 000000000000..59e3cd8377ec
--- /dev/null
+++ b/devtools/client/debugger/test/mochitest/browser_dbg-toolbox-unselected-pause.js
@@ -0,0 +1,54 @@
+/* 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/. */
+
+// Test that the debugger pauses in the omniscient browser toolbox even when it
+// hasn't been opened.
+
+"use strict";
+
+Services.scriptloader.loadSubScript(
+  "chrome://mochitests/content/browser/devtools/client/framework/test/helpers.js",
+  this
+);
+
+add_task(async function() {
+  await pushPref("devtools.browsertoolbox.fission", true);
+
+  // Make sure the toolbox opens with the webconsole initially selected.
+  await pushPref("devtools.browsertoolbox.panel", "webconsole");
+
+  const ToolboxTask = await initBrowserToolboxTask();
+  await ToolboxTask.importFunctions({
+    waitUntil,
+    waitForPaused,
+    isPaused,
+    waitForState,
+    info: () => {},
+    waitForSelectedSource,
+    waitForLoadedScopes: () => {},
+  });
+
+  addTab("data:text/html,<script>debugger;</script>");
+
+  // The debugger should automatically be selected.
+  await ToolboxTask.spawn(null, async () => {
+    await waitUntil(() => gToolbox.currentToolId == "jsdebugger");
+  });
+  ok(true, "Debugger selected");
+
+  // The debugger should pause.
+  await ToolboxTask.spawn(null, async () => {
+    // Wait for the debugger to finish loading.
+    await gToolbox.selectTool("jsdebugger");
+
+    const dbg = gToolbox.getCurrentPanel().panelWin.dbg;
+    await waitForPaused(dbg);
+    if (!gToolbox.isToolHighlighted("jsdebugger")) {
+      throw new Error("Debugger not highlighted");
+    }
+  });
+  ok(true, "Paused in new tab");
+
+  await ToolboxTask.destroy();
+});