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+# Performance test example: performance of click event in the inspector
+
+Let's look at a trivial but practical example and add a simple test to measure the performance of a click in the inspector.
+
+First we create a file under [tests/inspector](https://searchfox.org/mozilla-central/source/testing/talos/talos/tests/devtools/addon/content/tests/inspector) since we are writing an inspector test. We call the file `click.js`.
+
+We will use a dummy test document here: `data:text/html,click test document`.
+
+We prepare the imports needed to write the test, from head.js and inspector-helper.js:
+- `testSetup`, `testTeardown`, `openToolbox` and `runTest` from head.js
+- `reloadInspectorAndLog` from inspector-helper.js
+
+The full code for the test looks as follows:
+```
+const {
+  reloadInspectorAndLog,
+} = require("devtools/docs/tests/inspector-helpers");
+
+const {
+  openToolbox,
+  runTest,
+  testSetup,
+  testTeardown,
+} = require("devtools/docs/head");
+
+module.exports = async function() {
+  // Define here your custom document via a data URI:
+  const url = "data:text/html,click test document";
+
+  await testSetup(url);
+  const toolbox = await openToolbox("inspector");
+
+  const inspector = toolbox.getPanel("inspector");
+  const window = inspector.panelWin; // Get inspector's panel window object
+  const body = window.document.body;
+
+  await new Promise(resolve => {
+    const test = runTest("inspector.click");
+    body.addEventListener("click", function () {
+      test.done();
+      resolve();
+    }, { once: true });
+    body.click();
+  });
+
+  // Check if the inspector reload is impacted by click
+  await reloadInspectorAndLog("click", toolbox);
+
+  await testTeardown();
+}
+```
+
+Finally we add an entry in [damp-tests.js](https://searchfox.org/mozilla-central/source/testing/talos/talos/tests/devtools/addon/content/damp-tests.js):
+```
+  {
+    name: "inspector.click",
+    path: "inspector/click.js",
+    description:
+      "Measure the time to click in the inspector, and reload the inspector",
+  },
+```
+
+Then we can run our test with:
+```
+./mach talos-test --activeTests damp --subtest inspector.click
+```
+