diff --git a/testing/web-platform/tests/app-history/focus-reset/basic.html b/testing/web-platform/tests/app-history/focus-reset/basic.html
new file mode 100644
index 0000000000000..fb57cf864482a
--- /dev/null
+++ b/testing/web-platform/tests/app-history/focus-reset/basic.html
@@ -0,0 +1,64 @@
+<!doctype html>
+<script src="/resources/testharness.js"></script>
+<script src="/resources/testharnessreport.js"></script>
+
+<script type="module">
+import { testFocusWasReset, testFocusWasNotReset } from "./resources/helpers.mjs";
+
+test(() => {
+  let throwAssertionHappened = false;
+
+  appHistory.addEventListener("navigate", e => {
+    assert_throws_js(TypeError, () => {
+      e.transitionWhile(Promise.resolve(), { focusReset: "invalid" });
+    });
+    throwAssertionHappened = true;
+  }, { once: true });
+
+  appHistory.navigate("#1");
+  assert_true(throwAssertionHappened);
+}, "Invalid values for focusReset throw");
+
+testFocusWasNotReset(() => {
+  // Intentionally left blank.
+}, "Does not reset the focus when no navigate handler is present");
+
+testFocusWasReset(t => {
+  appHistory.addEventListener("navigate", e => {
+    e.transitionWhile(Promise.resolve());
+  }, { once: true });
+}, "Resets the focus when no focusReset option is provided");
+
+testFocusWasReset(t => {
+  appHistory.addEventListener("navigate", e => {
+    e.transitionWhile(Promise.resolve());
+  }, { once: true });
+}, "Resets the focus when focusReset is explicitly set to undefined");
+
+testFocusWasReset(t => {
+  appHistory.addEventListener("navigate", e => {
+    e.transitionWhile(new Promise(r => t.step_timeout(r, 5)));
+  }, { once: true });
+}, "Resets the focus when no focusReset option is provided (nontrivial fulfilled promise)");
+
+testFocusWasReset(t => {
+  appHistory.addEventListener("navigate", e => {
+    e.transitionWhile(Promise.reject());
+  }, { once: true });
+}, "Resets the focus when no focusReset option is provided (rejected promise)");
+
+testFocusWasReset(t => {
+  appHistory.addEventListener("navigate", e => {
+    e.transitionWhile(
+      Promise.resolve(),
+      { focusReset: "after-transition" }
+    );
+  }, { once: true });
+}, "Resets the focus when focusReset is explicitly set to 'after-transition'");
+
+testFocusWasNotReset(t => {
+  appHistory.addEventListener("navigate", e => {
+    e.transitionWhile(Promise.resolve(), { focusReset: "manual" });
+  });
+}, "Does not reset the focus when focusReset is set to 'manual'");
+</script>
diff --git a/testing/web-platform/tests/app-history/focus-reset/multiple-transitionWhile.html b/testing/web-platform/tests/app-history/focus-reset/multiple-transitionWhile.html
new file mode 100644
index 0000000000000..d38df573e5953
--- /dev/null
+++ b/testing/web-platform/tests/app-history/focus-reset/multiple-transitionWhile.html
@@ -0,0 +1,67 @@
+<!doctype html>
+<script src="/resources/testharness.js"></script>
+<script src="/resources/testharnessreport.js"></script>
+
+<script type="module">
+import { testFocusWasReset, testFocusWasNotReset } from "./resources/helpers.mjs";
+
+testFocusWasReset(t => {
+  appHistory.addEventListener("navigate", e => {
+    e.transitionWhile(Promise.resolve());
+  }, { once: true });
+
+  appHistory.addEventListener("navigate", e => {
+    e.transitionWhile(Promise.resolve(), { focusReset: "after-transition" });
+  }, { once: true });
+}, "(not provided) + after-transition");
+
+testFocusWasNotReset(t => {
+  appHistory.addEventListener("navigate", e => {
+    e.transitionWhile(Promise.resolve());
+  }, { once: true });
+
+  appHistory.addEventListener("navigate", e => {
+    e.transitionWhile(Promise.resolve(), { focusReset: "manual" });
+  }, { once: true });
+}, "(not provided) + manual");
+
+testFocusWasNotReset(t => {
+  appHistory.addEventListener("navigate", e => {
+    e.transitionWhile(Promise.resolve(), { focusReset: "after-transition" });
+  }, { once: true });
+
+  appHistory.addEventListener("navigate", e => {
+    e.transitionWhile(Promise.resolve(), { focusReset: "manual" });
+  }, { once: true });
+}, "after-transition + manual");
+
+testFocusWasReset(t => {
+  appHistory.addEventListener("navigate", e => {
+    e.transitionWhile(Promise.resolve(), { focusReset: "after-transition" });
+  }, { once: true });
+
+  appHistory.addEventListener("navigate", e => {
+    e.transitionWhile(Promise.resolve());
+  }, { once: true });
+}, "after-transition + (not provided)");
+
+testFocusWasReset(t => {
+  appHistory.addEventListener("navigate", e => {
+    e.transitionWhile(Promise.resolve(), { focusReset: "manual" });
+  }, { once: true });
+
+  appHistory.addEventListener("navigate", e => {
+    e.transitionWhile(Promise.resolve(), { focusReset: "after-transition" });
+  }, { once: true });
+}, "manual + after-transition");
+
+testFocusWasNotReset(t => {
+  appHistory.addEventListener("navigate", e => {
+    e.transitionWhile(Promise.resolve(), { focusReset: "manual" });
+  }, { once: true });
+
+  appHistory.addEventListener("navigate", e => {
+    e.transitionWhile(Promise.resolve());
+  }, { once: true });
+}, "manual + (not provided)");
+</script>
diff --git a/testing/web-platform/tests/app-history/focus-reset/resources/helpers.mjs b/testing/web-platform/tests/app-history/focus-reset/resources/helpers.mjs
new file mode 100644
index 0000000000000..e3012a0b12e61
--- /dev/null
+++ b/testing/web-platform/tests/app-history/focus-reset/resources/helpers.mjs
@@ -0,0 +1,45 @@
+// Usage note: if you use these more than once in a given file, be sure to
+// clean up any navigate event listeners, e.g. by using { once: true }, between
+// tests.
+
+export function testFocusWasReset(setupFunc, description) {
+  promise_test(async t => {
+    setupFunc(t);
+
+    const button = document.body.appendChild(document.createElement("button"));
+    t.add_cleanup(() => { button.remove(); });
+
+    assert_equals(document.activeElement, document.body, "Start on body");
+    button.focus();
+    assert_equals(document.activeElement, button, "focus() worked");
+
+    const { committed, finished } = appHistory.navigate("#" + location.hash.substring(1) + "1");
+
+    await committed;
+    assert_equals(document.activeElement, button, "Focus stays on the button during the transition");
+
+    await finished.catch(() => {});
+    assert_equals(document.activeElement, document.body, "Focus reset after the transition");
+  }, description);
+}
+
+export function testFocusWasNotReset(setupFunc, description) {
+  promise_test(async t => {
+    setupFunc(t);
+
+    const button = document.body.appendChild(document.createElement("button"));
+    t.add_cleanup(() => { button.remove(); });
+
+    assert_equals(document.activeElement, document.body, "Start on body");
+    button.focus();
+    assert_equals(document.activeElement, button, "focus() worked");
+
+    const { committed, finished } = appHistory.navigate("#" + location.hash.substring(1) + "1");
+
+    await committed;
+    assert_equals(document.activeElement, button, "Focus stays on the button during the transition");
+
+    await finished.catch(() => {});
+    assert_equals(document.activeElement, button, "Focus stays on the button after the transition");
+  }, description);
+}
