diff --git a/src/assert.js b/src/assert.js
index 25c541eb3..94cc8e7f7 100644
--- a/src/assert.js
+++ b/src/assert.js
@@ -81,7 +81,7 @@ class Assert {
   // Alias of pushResult.
   push (result, actual, expected, message, negative) {
     Logger.warn('assert.push is deprecated and will be removed in QUnit 3.0.' +
-      ' Please use assert.pushResult instead (https://qunitjs.com/api/assert/pushResult).');
+      ' Please use assert.pushResult instead. https://qunitjs.com/api/assert/pushResult');
 
     const currentAssert = this instanceof Assert ? this : config.current.assert;
     return currentAssert.pushResult({
diff --git a/src/core.js b/src/core.js
index 3c9404122..8bf783b05 100644
--- a/src/core.js
+++ b/src/core.js
@@ -124,7 +124,7 @@ extend(QUnit, {
 
   load: function () {
     Logger.warn('QUnit.load is deprecated and will be removed in QUnit 3.0.' +
-      ' Refer to <https://qunitjs.com/api/QUnit/load/>.');
+      ' https://qunitjs.com/api/QUnit/load/');
 
     QUnit.autostart();
   },
diff --git a/src/core/config.js b/src/core/config.js
index 0387d69bd..4e34207a2 100644
--- a/src/core/config.js
+++ b/src/core/config.js
@@ -127,6 +127,7 @@ const config = {
   // started: 0,
 
   // Internal state
+  _deprecated_timeout_shown: false,
   blocking: true,
   callbacks: {},
   modules: [],
diff --git a/src/test.js b/src/test.js
index 880cd7fde..11ca4385e 100644
--- a/src/test.js
+++ b/src/test.js
@@ -759,6 +759,18 @@ Test.prototype = {
           config.timeoutHandler(timeoutDuration),
           timeoutDuration
         );
+      } else {
+        clearTimeout(config.timeout);
+        config.timeout = setTimeout(
+          function () {
+            config.timeout = null;
+            if (!config._deprecated_timeout_shown) {
+              config._deprecated_timeout_shown = true;
+              Logger.warn(`Test "${test.testName}" took longer 3000ms, but no timeout was set. Set QUnit.config.testTimeout or call assert.timeout() to avoid a timeout in QUnit 3. https://qunitjs.com/api/config/testTimeout/`);
+            }
+          },
+          3000
+        );
       }
     }
 
diff --git a/test/cli/cli-main.js b/test/cli/cli-main.js
index 314d58384..4e919002f 100644
--- a/test/cli/cli-main.js
+++ b/test/cli/cli-main.js
@@ -16,6 +16,7 @@ QUnit.module('CLI Main', () => {
     // and only await/assert the already-started command.
     concurrentMapKeys(readFixtures(FIXTURES_DIR), 0, (runFixture) => runFixture()),
     async (assert, fixture) => {
+      assert.timeout(10000);
       const result = await fixture;
       assert.equal(result.snapshot, result.expected, result.name);
     }
diff --git a/test/cli/fixtures/config-testTimeout-deprecated.js b/test/cli/fixtures/config-testTimeout-deprecated.js
new file mode 100644
index 000000000..ab200bfc3
--- /dev/null
+++ b/test/cli/fixtures/config-testTimeout-deprecated.js
@@ -0,0 +1,20 @@
+QUnit.test('fast async', function (assert) {
+  var done = assert.async();
+  assert.true(true);
+  setTimeout(done, 7);
+});
+
+QUnit.test('slow async 1', function (assert) {
+  var done = assert.async();
+  assert.true(true);
+  setTimeout(done, 3500);
+});
+
+QUnit.test('slow async 2', function (assert) {
+  var done = assert.async();
+  assert.true(true);
+  setTimeout(done, 3500);
+});
+
+
+
diff --git a/test/cli/fixtures/config-testTimeout-deprecated.tap.txt b/test/cli/fixtures/config-testTimeout-deprecated.tap.txt
new file mode 100644
index 000000000..76646cd82
--- /dev/null
+++ b/test/cli/fixtures/config-testTimeout-deprecated.tap.txt
@@ -0,0 +1,14 @@
+# command: ["qunit", "config-testTimeout-deprecated.js"]
+
+TAP version 13
+ok 1 fast async
+ok 2 slow async 1
+ok 3 slow async 2
+1..3
+# pass 3
+# skip 0
+# todo 0
+# fail 0
+
+# stderr
+Test "slow async 1" took longer 3000ms, but no timeout was set. Set QUnit.config.testTimeout or call assert.timeout() to avoid a timeout in QUnit 3. https://qunitjs.com/api/config/testTimeout/