diff --git a/html/semantics/the-button-element/interest-target/interestelement-interface.tentative.html b/html/semantics/the-button-element/interest-target/interestelement-interface.tentative.html
index 8b1e37569559a4..bc68dc54577f44 100644
--- a/html/semantics/the-button-element/interest-target/interestelement-interface.tentative.html
+++ b/html/semantics/the-button-element/interest-target/interestelement-interface.tentative.html
@@ -84,82 +84,4 @@
       "interestTargetElement attribute value must be an instance of Element",
     );
   }, "interestTargetElement throws error on assignment of non Element");
-
-  test(function () {
-    assert_false(buttonInvoker.hasAttribute("interestaction"));
-    assert_equals(buttonInvoker.interestAction, "");
-    assert_false(aInvoker.hasAttribute("interestaction"));
-    assert_equals(aInvoker.interestAction, "");
-    assert_false(inputInvoker.hasAttribute("interestaction"));
-    assert_equals(inputInvoker.interestAction, "");
-  }, "interestAction reflects '' when attribute not present");
-
-  test(function () {
-    buttonInvoker.setAttribute("interestaction", "");
-    assert_equals(buttonInvoker.getAttribute("interestaction"), "");
-    assert_equals(buttonInvoker.interestAction, "");
-    aInvoker.setAttribute("interestaction", "");
-    assert_equals(aInvoker.getAttribute("interestaction"), "");
-    assert_equals(aInvoker.interestAction, "");
-    inputInvoker.setAttribute("interestaction", "");
-    assert_equals(inputInvoker.getAttribute("interestaction"), "");
-    assert_equals(inputInvoker.interestAction, "");
-  }, "interestAction reflects '' when attribute empty, setAttribute version");
-
-  test(function () {
-      buttonInvoker.interestAction = "";
-      assert_equals(buttonInvoker.getAttribute("interestaction"), "");
-      assert_equals(buttonInvoker.interestAction, "");
-      aInvoker.interestAction = "";
-      assert_equals(aInvoker.getAttribute("interestaction"), "");
-      assert_equals(aInvoker.interestAction, "");
-      inputInvoker.interestAction = "";
-      assert_equals(inputInvoker.getAttribute("interestaction"), "");
-      assert_equals(inputInvoker.interestAction, "");
-  }, "interestAction reflects '' when attribute empty, IDL setter version");
-
-  test(function () {
-      buttonInvoker.interestAction = "fooBarBaz";
-      assert_equals(buttonInvoker.getAttribute("interestaction"), "fooBarBaz");
-      assert_equals(buttonInvoker.interestAction, "fooBarBaz");
-      aInvoker.interestAction = "fooBarBaz";
-      assert_equals(aInvoker.getAttribute("interestaction"), "fooBarBaz");
-      assert_equals(aInvoker.interestAction, "fooBarBaz");
-      inputInvoker.interestAction = "fooBarBaz";
-      assert_equals(inputInvoker.getAttribute("interestaction"), "fooBarBaz");
-      assert_equals(inputInvoker.interestAction, "fooBarBaz");
-  }, "interestAction reflects same casing");
-
-  test(function () {
-      buttonInvoker.interestAction = [];
-      assert_equals(buttonInvoker.getAttribute("interestaction"), "");
-      assert_equals(buttonInvoker.interestAction, "");
-      aInvoker.interestAction = [];
-      assert_equals(aInvoker.getAttribute("interestaction"), "");
-      assert_equals(aInvoker.interestAction, "");
-      inputInvoker.interestAction = [];
-      assert_equals(inputInvoker.getAttribute("interestaction"), "");
-      assert_equals(inputInvoker.interestAction, "");
-  }, "interestAction reflects '' when attribute set to []");
-
-  test(function () {
-      buttonInvoker.interestAction = [1, 2, 3];
-      assert_equals(buttonInvoker.getAttribute("interestaction"), "1,2,3");
-      assert_equals(buttonInvoker.interestAction, "1,2,3");
-      aInvoker.interestAction = [1, 2, 3];
-      assert_equals(aInvoker.getAttribute("interestaction"), "1,2,3");
-      assert_equals(aInvoker.interestAction, "1,2,3");
-      inputInvoker.interestAction = [1, 2, 3];
-      assert_equals(inputInvoker.getAttribute("interestaction"), "1,2,3");
-      assert_equals(inputInvoker.interestAction, "1,2,3");
-  }, "interestAction reflects tostring value");
-
-  test(function () {
-      buttonInvoker.interestAction = {};
-      assert_equals(buttonInvoker.interestAction, "[object Object]");
-      aInvoker.interestAction = {};
-      assert_equals(aInvoker.interestAction, "[object Object]");
-      inputInvoker.interestAction = {};
-      assert_equals(inputInvoker.interestAction, "[object Object]");
-  }, "interestAction reflects tostring value 2");
 </script>
diff --git a/html/semantics/the-button-element/interest-target/interestevent-dispatch-shadow.tentative.html b/html/semantics/the-button-element/interest-target/interestevent-dispatch-shadow.tentative.html
index d96907ec84a439..9911357e94dd40 100644
--- a/html/semantics/the-button-element/interest-target/interestevent-dispatch-shadow.tentative.html
+++ b/html/semantics/the-button-element/interest-target/interestevent-dispatch-shadow.tentative.html
@@ -1,8 +1,11 @@
-<!doctype html>
+<!DOCTYPE html>
 <meta charset="utf-8" />
 <meta name="author" title="Keith Cirkel" href="mailto:keithamus@github.com" />
 <meta name="author" title="Luke Warlow" href="mailto:lwarlow@igalia.com" />
-<link rel="help" href="https://open-ui.org/components/interest-invokers.explainer/" />
+<link
+  rel="help"
+  href="https://open-ui.org/components/interest-invokers.explainer/"
+/>
 <script src="/resources/testharness.js"></script>
 <script src="/resources/testharnessreport.js"></script>
 <script src="/resources/testdriver.js"></script>
@@ -20,63 +23,35 @@
     const slot = shadow.appendChild(document.createElement("slot"));
     let childEvent = null;
     let childEventTarget = null;
-    let childEventInvoker = null;
+    let childEventSource = null;
     let hostEvent = null;
     let hostEventTarget = null;
-    let hostEventInvoker = null;
-    slot.addEventListener(
-      "interest",
-      (e) => {
+    let hostEventSource = null;
+    slot.addEventListener("interest", (e) => {
         childEvent = e;
         childEventTarget = e.target;
-        childEventInvoker = e.invoker;
-      },
-      { once: true },
-    );
-    host.addEventListener(
-      "interest",
-      (e) => {
+        childEventSource = e.source;
+      }, { once: true });
+    host.addEventListener("interest", (e) => {
         hostEvent = e;
         hostEventTarget = e.target;
-        hostEventInvoker = e.invoker;
-      },
-      { once: true },
-    );
+        hostEventSource = e.source;
+      }, { once: true });
     const event = new InterestEvent("interest", {
       bubbles: true,
-      invoker: slot,
+      source: slot,
       composed: true,
     });
     slot.dispatchEvent(event);
     assert_true(childEvent instanceof InterestEvent, "slot saw interest event");
-    assert_equals(
-      childEventTarget,
-      slot,
-      "target is child inside shadow boundary",
-    );
-    assert_equals(
-      childEventInvoker,
-      slot,
-      "invoker is child inside shadow boundary",
-    );
-    assert_equals(
-      hostEvent,
-      childEvent,
-      "event dispatch propagates across shadow boundary",
-    );
-    assert_equals(
-      hostEventTarget,
-      host,
-      "target is retargeted to shadowroot host",
-    );
-    assert_equals(
-      hostEventInvoker,
-      host,
-      "invoker is retargeted to shadowroot host",
-    );
-  }, "InterestEvent propagates across shadow boundaries retargeting invoker");
+    assert_equals(childEventTarget, slot, "target is child inside shadow boundary");
+    assert_equals(childEventSource, slot, "source is child inside shadow boundary");
+    assert_equals(hostEvent, childEvent, "event dispatch propagates across shadow boundary");
+    assert_equals(hostEventTarget, host, "target is retargeted to shadowroot host");
+    assert_equals(hostEventSource, host, "source is retargeted to shadowroot host");
+  }, "InterestEvent propagates across shadow boundaries retargeting invoker source");
 
-  test(function (t) {
+  promise_test(async (t) => {
     const host = document.createElement("div");
     document.body.append(host);
     t.add_cleanup(() => host.remove());
@@ -86,19 +61,16 @@
     button.interestTargetElement = interestee;
     let event = null;
     let eventTarget = null;
-    let eventInvoker = null;
-    interestee.addEventListener(
-      "interest",
-      (e) => {
+    let eventSource = null;
+    interestee.addEventListener("interest", (e) => {
         event = e;
         eventTarget = e.target;
-        eventInvoker = e.invoker;
-      },
-      { once: true },
-    );
-    button.focus();
+        eventSource = e.source;
+      },{ once: true });
+    await hoverOver(button);
+    assert_true(!!event,"InterestEvent gets fired");
     assert_true(event instanceof InterestEvent);
     assert_equals(eventTarget, interestee, "target is interestee");
-    assert_equals(eventInvoker, host, "interestee is host");
+    assert_equals(eventSource, host, "interestee is host");
   }, "cross shadow InterestEvent retargets interestee to host element");
 </script>
diff --git a/html/semantics/the-button-element/interest-target/interestevent-interface.tentative.html b/html/semantics/the-button-element/interest-target/interestevent-interface.tentative.html
index ed7d82f1fb7df8..9ed95a6a028983 100644
--- a/html/semantics/the-button-element/interest-target/interestevent-interface.tentative.html
+++ b/html/semantics/the-button-element/interest-target/interestevent-interface.tentative.html
@@ -16,152 +16,80 @@
 <script>
   test(function () {
     const event = new InterestEvent("test");
-    assert_equals(event.action, "");
-    assert_readonly(event, "action", "readonly attribute value");
-  }, "action is a readonly defaulting to ''");
+    assert_equals(event.source, null);
+    assert_readonly(event, "source", "readonly attribute value");
+  }, "source is readonly defaulting to null");
 
   test(function () {
-    const event = new InterestEvent("test");
-    assert_equals(event.invoker, null);
-    assert_readonly(event, "invoker", "readonly attribute value");
-  }, "invoker is readonly defaulting to null");
-
-  test(function () {
-    const event = new InterestEvent("test", { action: "sAmPle" });
-    assert_equals(event.action, "sAmPle");
-  }, "action reflects initialized attribute");
-
-  test(function () {
-    const event = new InterestEvent("test", { action: undefined });
-    assert_equals(event.action, "");
-  }, "action set to undefined");
-
-  test(function () {
-    const event = new InterestEvent("test", { action: null });
-    assert_equals(event.action, "null");
-  }, "action set to null");
-
-  test(function () {
-    const event = new InterestEvent("test", { action: false });
-    assert_equals(event.action, "false");
-  }, "action set to false");
-
-  test(function () {
-    const event = new InterestEvent("test", { action: "" });
-    assert_equals(event.action, "");
-  }, "action explicitly set to empty string");
-
-  test(function () {
-    const event = new InterestEvent("test", { action: true });
-    assert_equals(event.action, "true");
-  }, "action set to true");
-
-  test(function () {
-    const event = new InterestEvent("test", { action: 0.5 });
-    assert_equals(event.action, "0.5");
-  }, "action set to a number");
-
-  test(function () {
-    const event = new InterestEvent("test", { action: [] });
-    assert_equals(event.action, "");
-  }, "action set to []");
-
-  test(function () {
-    const event = new InterestEvent("test", { action: [1, 2, 3] });
-    assert_equals(event.action, "1,2,3");
-  }, "action set to [1, 2, 3]");
-
-  test(function () {
-    const event = new InterestEvent("test", { action: { sample: 0.5 } });
-    assert_equals(event.action, "[object Object]");
-  }, "action set to an object");
-
-  test(function () {
-    const event = new InterestEvent("test", {
-      action: {
-        toString() {
-          return "sample";
-        },
-      },
-    });
-    assert_equals(event.action, "sample");
-  }, "action set to an object with a toString function");
-
-  test(function () {
-    const eventInit = { action: "sample", invoker: document.body };
+    const eventInit = { source: document.body };
     const event = new InterestEvent("test", eventInit);
-    assert_equals(event.action, "sample");
-    assert_equals(event.invoker, document.body);
-  }, "InterestEventInit properties set value");
+    assert_equals(event.source, document.body);
+  }, "InterestEventInit properties set value (manual event)");
 
   test(function () {
     const eventInit = {
-      action: "open",
-      invoker: document.getElementById("div"),
+      source: document.getElementById("div"),
     };
     const event = new InterestEvent("beforetoggle", eventInit);
-    assert_equals(event.action, "open");
-    assert_equals(event.invoker, document.getElementById("div"));
-  }, "InterestEventInit properties set value 2");
+    assert_equals(event.source, document.getElementById("div"));
+  }, "InterestEventInit properties set value (beforetoggle event)");
 
   test(function () {
     const eventInit = {
-      action: "closed",
-      invoker: document.getElementById("button"),
+      source: document.getElementById("button"),
     };
     const event = new InterestEvent("toggle", eventInit);
-    assert_equals(event.action, "closed");
-    assert_equals(event.invoker, document.getElementById("button"));
-  }, "InterestEventInit properties set value 3");
+    assert_equals(event.source, document.getElementById("button"));
+  }, "InterestEventInit properties set value (toggle event)");
 
   test(function () {
-    const event = new InterestEvent("test", { invoker: undefined });
-    assert_equals(event.invoker, null);
-  }, "invoker set to undefined");
+    const event = new InterestEvent("test", { source: undefined });
+    assert_equals(event.source, null);
+  }, "source set to undefined");
 
   test(function () {
-    const event = new InterestEvent("test", { invoker: null });
-    assert_equals(event.invoker, null);
-  }, "invoker set to null");
+    const event = new InterestEvent("test", { source: null });
+    assert_equals(event.source, null);
+  }, "source set to null");
 
   test(function () {
     assert_throws_js(
       TypeError,
       function () {
-        new InterestEvent("test", { invoker: false });
+        new InterestEvent("test", { source: false });
       },
-      "invoker is not an object",
+      "source is not an object",
     );
-  }, "invoker set to false");
+  }, "source set to false");
 
   test(function () {
     assert_throws_js(
       TypeError,
       function () {
-        const event = new InterestEvent("test", { invoker: true });
+        const event = new InterestEvent("test", { source: true });
       },
-      "invoker is not an object",
+      "source is not an object",
     );
-  }, "invoker set to true");
+  }, "source set to true");
 
   test(function () {
     assert_throws_js(
       TypeError,
       function () {
-        const event = new InterestEvent("test", { invoker: {} });
+        const event = new InterestEvent("test", { source: {} });
       },
-      "invoker is not an object",
+      "source is not an object",
     );
-  }, "invoker set to {}");
+  }, "source set to {}");
 
   test(function () {
     assert_throws_js(
       TypeError,
       function () {
-        const eventInit = { action: "closed", invoker: new XMLHttpRequest() };
+        const eventInit = { source: new XMLHttpRequest() };
         const event = new InterestEvent("toggle", eventInit);
       },
-      "invoker is not an Element",
+      "source is not an Element",
     );
-  }, "invoker set to non-Element EventTarget");
+  }, "source set to non-Element EventTarget");
 </script>
diff --git a/html/semantics/the-button-element/interest-target/interesttarget-anchor-event-dispatch.tentative.html b/html/semantics/the-button-element/interest-target/interesttarget-anchor-event-dispatch.tentative.html
index b5a481ae08fc93..88a54c21f83bb1 100644
--- a/html/semantics/the-button-element/interest-target/interesttarget-anchor-event-dispatch.tentative.html
+++ b/html/semantics/the-button-element/interest-target/interesttarget-anchor-event-dispatch.tentative.html
@@ -15,33 +15,18 @@
 <button id="otherbutton">Other Button</button>
 
 <script>
-  promise_test(async function (t) {
-    t.add_cleanup(() => otherbutton.focus());
-    let event = null;
-    interestee.addEventListener("interest", (e) => (event = e), { once: true });
-    interestanchor.focus();
-    assert_true(event instanceof InterestEvent, "event is InterestEvent");
-    assert_equals(event.type, "interest", "type");
-    assert_equals(event.bubbles, false, "bubbles");
-    assert_equals(event.composed, true, "composed");
-    assert_equals(event.isTrusted, true, "isTrusted");
-    assert_equals(event.action, "", "action");
-    assert_equals(event.target, interestee, "target");
-    assert_equals(event.invoker, interestanchor, "invoker");
-  }, "InterestEvent dispatches on anchor focus");
-
   promise_test(async function (t) {
     t.add_cleanup(() => otherbutton.focus());
     let event = null;
     interestee.addEventListener("interest", (e) => (event = e), { once: true });
     await hoverOver(interestanchor);
+    assert_true(!!event, "InterestEvent is fired");
     assert_true(event instanceof InterestEvent, "event is InterestEvent");
     assert_equals(event.type, "interest", "type");
     assert_equals(event.bubbles, false, "bubbles");
     assert_equals(event.composed, true, "composed");
     assert_equals(event.isTrusted, true, "isTrusted");
-    assert_equals(event.action, "", "action");
     assert_equals(event.target, interestee, "target");
-    assert_equals(event.invoker, interestanchor, "invoker");
+    assert_equals(event.source, interestanchor, "source");
   }, "InterestEvent dispatches on anchor hover");
 </script>
diff --git a/html/semantics/the-button-element/interest-target/interesttarget-area-event-dispatch.tentative.html b/html/semantics/the-button-element/interest-target/interesttarget-area-event-dispatch.tentative.html
index 358acbb73ac3d6..5573235082617a 100644
--- a/html/semantics/the-button-element/interest-target/interesttarget-area-event-dispatch.tentative.html
+++ b/html/semantics/the-button-element/interest-target/interesttarget-area-event-dispatch.tentative.html
@@ -18,33 +18,18 @@
 <button id="otherbutton">Other Button</button>
 
 <script>
-  promise_test(async function (t) {
-    t.add_cleanup(() => otherbutton.focus());
-    let event = null;
-    interestee.addEventListener("interest", (e) => (event = e), { once: true });
-    interestarea.focus();
-    assert_true(event instanceof InterestEvent, "event is InterestEvent");
-    assert_equals(event.type, "interest", "type");
-    assert_equals(event.bubbles, false, "bubbles");
-    assert_equals(event.composed, true, "composed");
-    assert_equals(event.isTrusted, true, "isTrusted");
-    assert_equals(event.action, "", "action");
-    assert_equals(event.target, interestee, "target");
-    assert_equals(event.invoker, interestarea, "invoker");
-  }, "InterestEvent dispatches on area focus");
-
   promise_test(async function (t) {
     t.add_cleanup(() => otherbutton.focus());
     let event = null;
     interestee.addEventListener("interest", (e) => (event = e), { once: true });
     await hoverOver(interestarea);
+    assert_true(!!event, "InterestEvent is fired");
     assert_true(event instanceof InterestEvent, "event is InterestEvent");
     assert_equals(event.type, "interest", "type");
     assert_equals(event.bubbles, false, "bubbles");
     assert_equals(event.composed, true, "composed");
     assert_equals(event.isTrusted, true, "isTrusted");
-    assert_equals(event.action, "", "action");
     assert_equals(event.target, interestee, "target");
-    assert_equals(event.invoker, interestarea, "invoker");
+    assert_equals(event.source, interestarea, "source");
   }, "InterestEvent dispatches on area hover");
 </script>
diff --git a/html/semantics/the-button-element/interest-target/interesttarget-button-event-dispatch.tentative.html b/html/semantics/the-button-element/interest-target/interesttarget-button-event-dispatch.tentative.html
index 69126dbe14b01c..a9d68bb03fdd54 100644
--- a/html/semantics/the-button-element/interest-target/interesttarget-button-event-dispatch.tentative.html
+++ b/html/semantics/the-button-element/interest-target/interesttarget-button-event-dispatch.tentative.html
@@ -16,71 +16,23 @@
 
 <script>
   promise_test(async function (t) {
-    t.add_cleanup(() => otherbutton.focus());
-    let event = null;
-    interestee.addEventListener("interest", (e) => (event = e), { once: true });
-    interestbutton.focus();
-    assert_true(event instanceof InterestEvent, "event is InterestEvent");
-    assert_equals(event.type, "interest", "type");
-    assert_equals(event.bubbles, false, "bubbles");
-    assert_equals(event.composed, true, "composed");
-    assert_equals(event.isTrusted, true, "isTrusted");
-    assert_equals(event.action, "", "action");
-    assert_equals(event.target, interestee, "target");
-    assert_equals(event.invoker, interestbutton, "invoker");
-  }, "InterestEvent dispatches on button focus");
-
-  promise_test(async function (t) {
-    t.add_cleanup(() => otherbutton.focus());
     let event = null;
     interestee.addEventListener("interest", (e) => (event = e), { once: true });
     await hoverOver(interestbutton);
+    assert_true(!!event, "InterestEvent is fired");
     assert_true(event instanceof InterestEvent, "event is InterestEvent");
     assert_equals(event.type, "interest", "type");
     assert_equals(event.bubbles, false, "bubbles");
     assert_equals(event.composed, true, "composed");
     assert_equals(event.isTrusted, true, "isTrusted");
-    assert_equals(event.action, "", "action");
     assert_equals(event.target, interestee, "target");
-    assert_equals(event.invoker, interestbutton, "invoker");
+    assert_equals(event.source, interestbutton, "source");
   }, "InterestEvent dispatches on button hover");
 
   promise_test(async function (t) {
-    t.add_cleanup(() => otherbutton.focus());
-    let event = null;
-    interestee.addEventListener("interest", (e) => (event = e), { once: true });
-    interestbutton.interestAction = "fooBar";
-    interestbutton.focus();
-    assert_true(event instanceof InterestEvent, "event is InterestEvent");
-    assert_equals(event.type, "interest", "type");
-    assert_equals(event.bubbles, false, "bubbles");
-    assert_equals(event.composed, true, "composed");
-    assert_equals(event.isTrusted, true, "isTrusted");
-    assert_equals(event.action, "fooBar", "action");
-    assert_equals(event.target, interestee, "target");
-    assert_equals(event.invoker, interestbutton, "invoker");
-  }, "event action is set to interestAction");
-
-  promise_test(async function (t) {
-    t.add_cleanup(() => otherbutton.focus());
-    let event = null;
-    interestee.addEventListener("interest", (e) => (event = e), { once: true });
-    interestbutton.setAttribute("interestaction", "BaRbAz");
-    interestbutton.focus();
-    assert_true(event instanceof InterestEvent, "event is InterestEvent");
-    assert_equals(event.type, "interest", "type");
-    assert_equals(event.bubbles, false, "bubbles");
-    assert_equals(event.composed, true, "composed");
-    assert_equals(event.isTrusted, true, "isTrusted");
-    assert_equals(event.action, "BaRbAz", "action");
-    assert_equals(event.target, interestee, "target");
-    assert_equals(event.invoker, interestbutton, "invoker");
-  }, "event action is set to interestaction attribute");
-
-  promise_test(async function (t) {
-    t.add_cleanup(() => {
+    t.add_cleanup(async () => {
       interestbutton.removeAttribute('disabled');
-      otherbutton.focus();
+      await hoverOver(otherbutton);
     });
     let called = false;
     interestee.addEventListener(
@@ -91,34 +43,27 @@
       { once: true },
     );
     interestbutton.setAttribute("disabled", "");
-    interestbutton.focus();
+    await hoverOver(interestbutton);
     assert_false(called, "event was not called");
   }, "event does not dispatch if invoker is disabled");
 
   promise_test(async function (t) {
     svgInterestee = document.createElementNS('http://www.w3.org/2000/svg', 'svg');
-    t.add_cleanup(() => {
+    t.add_cleanup(async () => {
       interestbutton.interestTargetElement = interestee;
       svgInterestee.remove();
-      otherbutton.focus();
+      await hoverOver(otherbutton);
     });
     document.body.append(svgInterestee);
     let called = false;
     assert_false(svgInterestee instanceof HTMLElement);
     assert_true(svgInterestee instanceof Element);
     let event = null;
-    svgInterestee.addEventListener(
-      "interest",
-      (e) => {
-        event = e;
-        called = true;
-      },
-      { once: true },
-    );
+    svgInterestee.addEventListener("interest", (e) => (event = e), { once: true });
     interestbutton.interestTargetElement = svgInterestee;
-    interestbutton.focus();
-    assert_true(called, "event was called");
-    assert_equals(event.invoker, interestbutton, "event.invoker is set to right element");
+    await hoverOver(interestbutton);
+    assert_true(!!event, "InterestEvent is fired");
+    assert_equals(event.source, interestbutton, "event.source is set to right element");
     assert_equals(event.target, svgInterestee, "event.target is set to right element");
   }, "event dispatches if interestee is non-HTML Element");
 </script>
diff --git a/html/semantics/the-button-element/interest-target/interesttarget-on-popover-behavior.tentative.html b/html/semantics/the-button-element/interest-target/interesttarget-on-popover-behavior.tentative.html
index fd0a77b9359317..cbb5e4014eed14 100644
--- a/html/semantics/the-button-element/interest-target/interesttarget-on-popover-behavior.tentative.html
+++ b/html/semantics/the-button-element/interest-target/interesttarget-on-popover-behavior.tentative.html
@@ -17,44 +17,17 @@
 <button id="otherbutton">Other button</button>
 
 <script>
-  function reset() {
+  async function reset() {
       hoverOver(otherbutton);
-      otherbutton.focus();
+      await hoverOver(otherbutton);
       interestee.hidePopover();
-      interestbutton.removeAttribute("interestaction");
   }
-
-  // auto
-
   promise_test(async function (t) {
     t.add_cleanup(reset);
     assert_false(interestee.matches(":popover-open"));
     await hoverOver(interestbutton);
     assert_true(interestee.matches(":popover-open"));
-  }, "hover interest invoking (as auto) closed popover opens");
-
-  promise_test(async function (t) {
-    t.add_cleanup(reset);
-    interestee.showPopover();
-    assert_true(interestee.matches(":popover-open"));
-    await hoverOver(interestbutton);
-    assert_false(interestee.matches(":popover-open"));
-  }, "hover interest invoking (as auto) open popover closes");
-
-  promise_test(async function (t) {
-    t.add_cleanup(reset);
-    assert_false(interestee.matches(":popover-open"));
-    interestbutton.focus();
-    assert_true(interestee.matches(":popover-open"));
-  }, "focus interest invoking (as auto) closed popover opens");
-
-  promise_test(async function (t) {
-    t.add_cleanup(reset);
-    interestee.showPopover();
-    assert_true(interestee.matches(":popover-open"));
-    interestbutton.focus();
-    assert_false(interestee.matches(":popover-open"));
-  }, "focus interest invoking (as auto) open popover closes");
+  }, "hover interest invoking closed popover opens");
 
   promise_test(async function (t) {
     t.add_cleanup(reset);
@@ -64,50 +37,5 @@
     });
     await hoverOver(interestbutton);
     assert_false(interestee.matches(":popover-open"));
-  }, "interest invoking (as auto) closed popover with preventDefault does not open");
-
-  // togglepopover
-
-  promise_test(async function (t) {
-    t.add_cleanup(reset);
-    assert_false(interestee.matches(":popover-open"));
-    interestbutton.setAttribute("interestaction", "toggle-popover");
-    await hoverOver(interestbutton);
-    assert_true(interestee.matches(":popover-open"));
-  }, "hover interest invoking (as togglepopover) closed popover opens");
-
-  promise_test(async function (t) {
-    t.add_cleanup(reset);
-    interestee.showPopover();
-    assert_true(interestee.matches(":popover-open"));
-    interestbutton.setAttribute("interestaction", "toggle-popover");
-    await hoverOver(interestbutton);
-    assert_false(interestee.matches(":popover-open"));
-  }, "hover interest invoking (as togglepopover) open popover closes");
-
-  promise_test(async function (t) {
-    t.add_cleanup(reset);
-    assert_false(interestee.matches(":popover-open"));
-    interestbutton.setAttribute("interestaction", "toggle-popover");
-    interestbutton.focus();
-    assert_true(interestee.matches(":popover-open"));
-  }, "focus interest invoking (as togglepopover) closed popover opens");
-
-  promise_test(async function (t) {
-    t.add_cleanup(reset);
-    interestee.showPopover();
-    assert_true(interestee.matches(":popover-open"));
-    interestbutton.setAttribute("interestaction", "toggle-popover");
-    interestbutton.focus();
-    assert_false(interestee.matches(":popover-open"));
-  }, "focus interest invoking (as togglepopover) open popover closes");
-
-  promise_test(async function (t) {
-    t.add_cleanup(reset);
-    assert_false(interestee.matches(":popover-open"));
-    interestbutton.setAttribute("interestaction", "tOgGlE-pOpOvEr");
-    interestbutton.focus();
-    assert_true(interestee.matches(":popover-open"));
-  }, "interest invoking (as togglepopover - case insensitive) closed popover opens");
-
+  }, "interest invoking closed popover with preventDefault does not open");
 </script>
diff --git a/html/semantics/the-button-element/interest-target/interesttarget-svg-a-event-dispatch.tentative.html b/html/semantics/the-button-element/interest-target/interesttarget-svg-a-event-dispatch.tentative.html
index 7fb4b1c19d6819..8208c8d56af9dd 100644
--- a/html/semantics/the-button-element/interest-target/interesttarget-svg-a-event-dispatch.tentative.html
+++ b/html/semantics/the-button-element/interest-target/interesttarget-svg-a-event-dispatch.tentative.html
@@ -20,32 +20,19 @@
 
 <script>
   promise_test(async function (t) {
-    t.add_cleanup(() => otherbutton.focus());
-    let event = null;
-    interestee.addEventListener("interest", (e) => (event = e), { once: true });
-    interestsvga.focus();
-    assert_true(event instanceof InterestEvent, "event is InterestEvent");
-    assert_equals(event.type, "interest", "type");
-    assert_equals(event.bubbles, false, "bubbles");
-    assert_equals(event.composed, true, "composed");
-    assert_equals(event.isTrusted, true, "isTrusted");
-    assert_equals(event.action, "", "action");
-    assert_equals(event.target, interestee, "target");
-    assert_equals(event.invoker, interestsvga, "invoker");
-  }, "InterestEvent dispatches on svg a focus");
-
-  promise_test(async function (t) {
-    t.add_cleanup(() => otherbutton.focus());
+    t.add_cleanup(async () => {
+      await hoverOver(otherbutton);
+    });
     let event = null;
     interestee.addEventListener("interest", (e) => (event = e), { once: true });
     await hoverOver(interestsvga);
+    assert_true(!!event, "InterestEvent is fired");
     assert_true(event instanceof InterestEvent, "event is InterestEvent");
     assert_equals(event.type, "interest", "type");
     assert_equals(event.bubbles, false, "bubbles");
     assert_equals(event.composed, true, "composed");
     assert_equals(event.isTrusted, true, "isTrusted");
-    assert_equals(event.action, "", "action");
     assert_equals(event.target, interestee, "target");
-    assert_equals(event.invoker, interestsvga, "invoker");
+    assert_equals(event.source, interestsvga, "source");
   }, "InterestEvent dispatches on svg a hover");
 </script>