diff --git a/testing/web-platform/tests/.well-known/origin-policy b/testing/web-platform/tests/.well-known/origin-policy
new file mode 100644
index 0000000000000..df2b83256c226
--- /dev/null
+++ b/testing/web-platform/tests/.well-known/origin-policy
@@ -0,0 +1,18 @@
+import os
+import glob
+
+
+def main(request, response):
+    host_piece = request.url_parts.hostname.split(".")[0]
+
+    filepath_pattern = os.path.normpath(os.path.join(os.path.dirname(os.path.abspath(
+        __file__)), "../origin-policy/policies/", "{} *.json".format(host_piece)))
+
+    matches = glob.glob(filepath_pattern)
+
+    if len(matches) != 1:
+        return 404, [], '{} origin policies found at a path matching "{}"'.format(len(matches), filepath_pattern)
+
+    with open(matches[0]) as f:
+        data = f.read()
+        return 200, [('Content-Type', 'application/originpolicy+json')], data
diff --git a/testing/web-platform/tests/.well-known/origin-policy/policy-content-security-comma-in-policy b/testing/web-platform/tests/.well-known/origin-policy/policy-content-security-comma-in-policy
deleted file mode 100644
index 42990f93e6d27..0000000000000
--- a/testing/web-platform/tests/.well-known/origin-policy/policy-content-security-comma-in-policy
+++ /dev/null
@@ -1,5 +0,0 @@
-{
-  "content_security": {
-    "policies": ["script-src 'self' 'unsafe-inline', img-src 'none'"]
-  }
-}
diff --git a/testing/web-platform/tests/.well-known/origin-policy/policy-content-security-double-content-security b/testing/web-platform/tests/.well-known/origin-policy/policy-content-security-double-content-security
deleted file mode 100644
index be9b3750647d1..0000000000000
--- a/testing/web-platform/tests/.well-known/origin-policy/policy-content-security-double-content-security
+++ /dev/null
@@ -1,8 +0,0 @@
-{
-  "content_security": {
-    "policies": ["script-src 'self' 'unsafe-inline'"]
-  },
-  "content_security": {
-    "policies": ["img-src 'none'"]
-  }
-}
diff --git a/testing/web-platform/tests/.well-known/origin-policy/policy-content-security-double-policies b/testing/web-platform/tests/.well-known/origin-policy/policy-content-security-double-policies
deleted file mode 100644
index 2e625c5c46389..0000000000000
--- a/testing/web-platform/tests/.well-known/origin-policy/policy-content-security-double-policies
+++ /dev/null
@@ -1,6 +0,0 @@
-{
-  "content_security": {
-    "policies": ["script-src 'self' 'unsafe-inline'"],
-    "policies": ["img-src 'none'"]
-  }
-}
diff --git a/testing/web-platform/tests/.well-known/origin-policy/policy-content-security-noimg-report-only b/testing/web-platform/tests/.well-known/origin-policy/policy-content-security-noimg-report-only
deleted file mode 100644
index 13c662ef2d6e1..0000000000000
--- a/testing/web-platform/tests/.well-known/origin-policy/policy-content-security-noimg-report-only
+++ /dev/null
@@ -1,5 +0,0 @@
-{
-  "content_security": {
-    "policies_report_only": ["img-src 'none'"]
-  }
-}
diff --git a/testing/web-platform/tests/.well-known/origin-policy/policy-content-security-non-object b/testing/web-platform/tests/.well-known/origin-policy/policy-content-security-non-object
deleted file mode 100644
index 7f6e138364012..0000000000000
--- a/testing/web-platform/tests/.well-known/origin-policy/policy-content-security-non-object
+++ /dev/null
@@ -1,3 +0,0 @@
-{
-  "content_security": ["script-src 'self' 'unsafe-inline'"]
-}
diff --git a/testing/web-platform/tests/.well-known/origin-policy/policy-content-security-non-string b/testing/web-platform/tests/.well-known/origin-policy/policy-content-security-non-string
deleted file mode 100644
index 8649b17c4d8e7..0000000000000
--- a/testing/web-platform/tests/.well-known/origin-policy/policy-content-security-non-string
+++ /dev/null
@@ -1,5 +0,0 @@
-{
-  "content_security": {
-    "policies": [["script-src 'self' 'unsafe-inline'"]]
-  }
-}
diff --git a/testing/web-platform/tests/.well-known/origin-policy/policy-content-security-valid b/testing/web-platform/tests/.well-known/origin-policy/policy-content-security-valid
deleted file mode 100644
index d4babb7949eef..0000000000000
--- a/testing/web-platform/tests/.well-known/origin-policy/policy-content-security-valid
+++ /dev/null
@@ -1,5 +0,0 @@
-{
-  "content_security": {
-    "policies": ["script-src 'self' 'unsafe-inline'"]
-  }
-}
diff --git a/testing/web-platform/tests/.well-known/origin-policy/policy-content-security-valid-with-multi-item-array b/testing/web-platform/tests/.well-known/origin-policy/policy-content-security-valid-with-multi-item-array
deleted file mode 100644
index 45ec32200d5f6..0000000000000
--- a/testing/web-platform/tests/.well-known/origin-policy/policy-content-security-valid-with-multi-item-array
+++ /dev/null
@@ -1,5 +0,0 @@
-{
-  "content_security": {
-    "policies": ["script-src 'self' 'unsafe-inline'", "img-src 'none'"]
-  }
-}
diff --git a/testing/web-platform/tests/.well-known/origin-policy/policy-content-security-valid-with-semicolon b/testing/web-platform/tests/.well-known/origin-policy/policy-content-security-valid-with-semicolon
deleted file mode 100644
index e777d5c96d592..0000000000000
--- a/testing/web-platform/tests/.well-known/origin-policy/policy-content-security-valid-with-semicolon
+++ /dev/null
@@ -1,5 +0,0 @@
-{
-  "content_security": {
-    "policies": ["script-src 'self' 'unsafe-inline'; img-src 'none'"]
-  }
-}
diff --git a/testing/web-platform/tests/.well-known/origin-policy/policy-csp-1 b/testing/web-platform/tests/.well-known/origin-policy/policy-csp-1
deleted file mode 100644
index d4babb7949eef..0000000000000
--- a/testing/web-platform/tests/.well-known/origin-policy/policy-csp-1
+++ /dev/null
@@ -1,5 +0,0 @@
-{
-  "content_security": {
-    "policies": ["script-src 'self' 'unsafe-inline'"]
-  }
-}
diff --git a/testing/web-platform/tests/.well-known/origin-policy/policy-csp-2 b/testing/web-platform/tests/.well-known/origin-policy/policy-csp-2
deleted file mode 100644
index 34a6c5c873b57..0000000000000
--- a/testing/web-platform/tests/.well-known/origin-policy/policy-csp-2
+++ /dev/null
@@ -1,5 +0,0 @@
-{
-  "content_security": {
-    "policies": ["script-src 'self' 'nonce-test'"]
-  }
-}
diff --git a/testing/web-platform/tests/.well-known/origin-policy/policy-features-comma-in-policy b/testing/web-platform/tests/.well-known/origin-policy/policy-features-comma-in-policy
deleted file mode 100644
index e991c788f24a1..0000000000000
--- a/testing/web-platform/tests/.well-known/origin-policy/policy-features-comma-in-policy
+++ /dev/null
@@ -1,5 +0,0 @@
-{
-  "features": {
-    "policy": "camera 'self' https://example.com/, geolocation 'self' https://example.com/"
-  }
-}
diff --git a/testing/web-platform/tests/.well-known/origin-policy/policy-features-double-features b/testing/web-platform/tests/.well-known/origin-policy/policy-features-double-features
deleted file mode 100644
index 583f1eaa2fcda..0000000000000
--- a/testing/web-platform/tests/.well-known/origin-policy/policy-features-double-features
+++ /dev/null
@@ -1,8 +0,0 @@
-{
-  "features": {
-    "policy": "camera 'self' https://example.com/"
-  },
-  "features": {
-    "policy": "geolocation 'self' https://example.com/"
-  }
-}
diff --git a/testing/web-platform/tests/.well-known/origin-policy/policy-features-double-policy b/testing/web-platform/tests/.well-known/origin-policy/policy-features-double-policy
deleted file mode 100644
index fb216bc472983..0000000000000
--- a/testing/web-platform/tests/.well-known/origin-policy/policy-features-double-policy
+++ /dev/null
@@ -1,6 +0,0 @@
-{
-  "features": {
-    "policy": "camera 'self' https://example.com/",
-    "policy": "geolocation 'self' https://example.com/"
-  }
-}
diff --git a/testing/web-platform/tests/.well-known/origin-policy/policy-features-non-object b/testing/web-platform/tests/.well-known/origin-policy/policy-features-non-object
deleted file mode 100644
index b4d255440dc4b..0000000000000
--- a/testing/web-platform/tests/.well-known/origin-policy/policy-features-non-object
+++ /dev/null
@@ -1,3 +0,0 @@
-{
-  "features": "camera 'self' https://example.com/"
-}
diff --git a/testing/web-platform/tests/.well-known/origin-policy/policy-features-non-string b/testing/web-platform/tests/.well-known/origin-policy/policy-features-non-string
deleted file mode 100644
index 8b758c7f61779..0000000000000
--- a/testing/web-platform/tests/.well-known/origin-policy/policy-features-non-string
+++ /dev/null
@@ -1,5 +0,0 @@
-{
-  "features": {
-    "policy": ["camera 'self' https://example.com/"]
-  }
-}
diff --git a/testing/web-platform/tests/.well-known/origin-policy/policy-features-valid b/testing/web-platform/tests/.well-known/origin-policy/policy-features-valid
deleted file mode 100644
index 22ef8992cf7b5..0000000000000
--- a/testing/web-platform/tests/.well-known/origin-policy/policy-features-valid
+++ /dev/null
@@ -1,5 +0,0 @@
-{
-  "features": {
-    "policy": "camera 'self' https://example.com/; geolocation 'self' https://example.com/"
-  }
-}
diff --git a/testing/web-platform/tests/origin-policy/content-security/comma-in-policy.https.html b/testing/web-platform/tests/origin-policy/content-security/comma-in-policy.https.html
index 88d72446392e6..07d10811f0bf8 100644
--- a/testing/web-platform/tests/origin-policy/content-security/comma-in-policy.https.html
+++ b/testing/web-platform/tests/origin-policy/content-security/comma-in-policy.https.html
@@ -3,9 +3,14 @@
 <title>Commas in "content_security/policy" cause parse errors and thus no CSP</title>
 <script src="/resources/testharness.js"></script>
 <script src="/resources/testharnessreport.js"></script>
-<script src="helper.js"></script>
+<script src="../resources/origin-policy-test-runner.js"></script>
+
+<div id="log"></div>
 
 <script>
 "use strict";
-runCSPTest({ unsafeEval: true });
+runTestsInSubframe({
+  hostname: "op1",
+  testJS: "resources/allow-unsafe-eval.mjs"
+});
 </script>
diff --git a/testing/web-platform/tests/origin-policy/content-security/comma-in-policy.https.html.headers b/testing/web-platform/tests/origin-policy/content-security/comma-in-policy.https.html.headers
deleted file mode 100644
index 32e453ab20de0..0000000000000
--- a/testing/web-platform/tests/origin-policy/content-security/comma-in-policy.https.html.headers
+++ /dev/null
@@ -1 +0,0 @@
-Sec-Origin-Policy: policy=policy-content-security-comma-in-policy
diff --git a/testing/web-platform/tests/origin-policy/content-security/double-content-security.https.html b/testing/web-platform/tests/origin-policy/content-security/double-content-security.https.html
index 99046803c9fe3..357bd7669a668 100644
--- a/testing/web-platform/tests/origin-policy/content-security/double-content-security.https.html
+++ b/testing/web-platform/tests/origin-policy/content-security/double-content-security.https.html
@@ -3,11 +3,14 @@
 <title>Of two "content_security" items only the second counts</title>
 <script src="/resources/testharness.js"></script>
 <script src="/resources/testharnessreport.js"></script>
-<script src="helper.js"></script>
+<script src="../resources/origin-policy-test-runner.js"></script>
 
-<body>
+<div id="log"></div>
 
 <script>
 "use strict";
-runCSPTest({ unsafeEval: true, img: false });
+runTestsInSubframe({
+  hostname: "op2",
+  testJS: "resources/allow-unsafe-eval-disallow-images.mjs"
+});
 </script>
diff --git a/testing/web-platform/tests/origin-policy/content-security/double-content-security.https.html.headers b/testing/web-platform/tests/origin-policy/content-security/double-content-security.https.html.headers
deleted file mode 100644
index a380b053c270c..0000000000000
--- a/testing/web-platform/tests/origin-policy/content-security/double-content-security.https.html.headers
+++ /dev/null
@@ -1 +0,0 @@
-Sec-Origin-Policy: policy=policy-content-security-double-content-security
diff --git a/testing/web-platform/tests/origin-policy/content-security/double-policies.https.html b/testing/web-platform/tests/origin-policy/content-security/double-policies.https.html
index 925b9d5a31e10..327670fcad0b3 100644
--- a/testing/web-platform/tests/origin-policy/content-security/double-policies.https.html
+++ b/testing/web-platform/tests/origin-policy/content-security/double-policies.https.html
@@ -3,11 +3,14 @@
 <title>Of two "content_security/policies" items only the second counts</title>
 <script src="/resources/testharness.js"></script>
 <script src="/resources/testharnessreport.js"></script>
-<script src="helper.js"></script>
+<script src="../resources/origin-policy-test-runner.js"></script>
 
-<body>
+<div id="log"></div>
 
 <script>
 "use strict";
-runCSPTest({ unsafeEval: true, img: false });
+runTestsInSubframe({
+  hostname: "op3",
+  testJS: "resources/allow-unsafe-eval-disallow-images.mjs"
+});
 </script>
diff --git a/testing/web-platform/tests/origin-policy/content-security/double-policies.https.html.headers b/testing/web-platform/tests/origin-policy/content-security/double-policies.https.html.headers
deleted file mode 100644
index 23f1d1434057d..0000000000000
--- a/testing/web-platform/tests/origin-policy/content-security/double-policies.https.html.headers
+++ /dev/null
@@ -1 +0,0 @@
-Sec-Origin-Policy: policy=policy-content-security-double-policies
diff --git a/testing/web-platform/tests/origin-policy/content-security/non-array.https.html b/testing/web-platform/tests/origin-policy/content-security/non-array.https.html
index 78a67e16eb9d3..c95b5a15b0e64 100644
--- a/testing/web-platform/tests/origin-policy/content-security/non-array.https.html
+++ b/testing/web-platform/tests/origin-policy/content-security/non-array.https.html
@@ -3,9 +3,14 @@
 <title>Non-array "content_security/policies" member must be ignored</title>
 <script src="/resources/testharness.js"></script>
 <script src="/resources/testharnessreport.js"></script>
-<script src="helper.js"></script>
+<script src="../resources/origin-policy-test-runner.js"></script>
+
+<div id="log"></div>
 
 <script>
 "use strict";
-runCSPTest({ unsafeEval: true });
+runTestsInSubframe({
+  hostname: "op4",
+  testJS: "resources/allow-unsafe-eval.mjs"
+});
 </script>
diff --git a/testing/web-platform/tests/origin-policy/content-security/non-array.https.html.headers b/testing/web-platform/tests/origin-policy/content-security/non-array.https.html.headers
deleted file mode 100644
index 31e6f375ef967..0000000000000
--- a/testing/web-platform/tests/origin-policy/content-security/non-array.https.html.headers
+++ /dev/null
@@ -1 +0,0 @@
-Sec-Origin-Policy: policy=policy-content-security-non-array
diff --git a/testing/web-platform/tests/origin-policy/content-security/non-object.https.html b/testing/web-platform/tests/origin-policy/content-security/non-object.https.html
index 359c6c7692294..220136c4d050b 100644
--- a/testing/web-platform/tests/origin-policy/content-security/non-object.https.html
+++ b/testing/web-platform/tests/origin-policy/content-security/non-object.https.html
@@ -3,9 +3,14 @@
 <title>Non-object "content_security" member must be ignored</title>
 <script src="/resources/testharness.js"></script>
 <script src="/resources/testharnessreport.js"></script>
-<script src="helper.js"></script>
+<script src="../resources/origin-policy-test-runner.js"></script>
+
+<div id="log"></div>
 
 <script>
 "use strict";
-runCSPTest({ unsafeEval: true });
+runTestsInSubframe({
+  hostname: "op5",
+  testJS: "resources/allow-unsafe-eval.mjs"
+});
 </script>
diff --git a/testing/web-platform/tests/origin-policy/content-security/non-object.https.html.headers b/testing/web-platform/tests/origin-policy/content-security/non-object.https.html.headers
deleted file mode 100644
index 812ea9445eca1..0000000000000
--- a/testing/web-platform/tests/origin-policy/content-security/non-object.https.html.headers
+++ /dev/null
@@ -1 +0,0 @@
-Sec-Origin-Policy: policy=policy-content-security-non-object
diff --git a/testing/web-platform/tests/origin-policy/content-security/non-string.https.html b/testing/web-platform/tests/origin-policy/content-security/non-string.https.html
index 8af3c1c4dff13..57c29fe265beb 100644
--- a/testing/web-platform/tests/origin-policy/content-security/non-string.https.html
+++ b/testing/web-platform/tests/origin-policy/content-security/non-string.https.html
@@ -3,9 +3,14 @@
 <title>Non-string "content_security/policies" array member must be ignored</title>
 <script src="/resources/testharness.js"></script>
 <script src="/resources/testharnessreport.js"></script>
-<script src="helper.js"></script>
+<script src="../resources/origin-policy-test-runner.js"></script>
+
+<div id="log"></div>
 
 <script>
 "use strict";
-runCSPTest({ unsafeEval: true });
+runTestsInSubframe({
+  hostname: "op6",
+  testJS: "resources/allow-unsafe-eval.mjs"
+});
 </script>
diff --git a/testing/web-platform/tests/origin-policy/content-security/non-string.https.html.headers b/testing/web-platform/tests/origin-policy/content-security/non-string.https.html.headers
deleted file mode 100644
index 0b9ce2ee3f84c..0000000000000
--- a/testing/web-platform/tests/origin-policy/content-security/non-string.https.html.headers
+++ /dev/null
@@ -1 +0,0 @@
-Sec-Origin-Policy: policy=policy-content-security-non-string
diff --git a/testing/web-platform/tests/origin-policy/content-security/resources/allow-unsafe-eval-disallow-images.mjs b/testing/web-platform/tests/origin-policy/content-security/resources/allow-unsafe-eval-disallow-images.mjs
new file mode 100644
index 0000000000000..8715e74e5df81
--- /dev/null
+++ b/testing/web-platform/tests/origin-policy/content-security/resources/allow-unsafe-eval-disallow-images.mjs
@@ -0,0 +1,3 @@
+import { runCSPTest } from "./helper.mjs";
+
+runCSPTest({ unsafeEval: true, img: false });
diff --git a/testing/web-platform/tests/origin-policy/content-security/resources/allow-unsafe-eval.mjs b/testing/web-platform/tests/origin-policy/content-security/resources/allow-unsafe-eval.mjs
new file mode 100644
index 0000000000000..bd6ca6f8bbd1e
--- /dev/null
+++ b/testing/web-platform/tests/origin-policy/content-security/resources/allow-unsafe-eval.mjs
@@ -0,0 +1,3 @@
+import { runCSPTest } from "./helper.mjs";
+
+runCSPTest({ unsafeEval: true });
diff --git a/testing/web-platform/tests/origin-policy/content-security/resources/disallow-unsafe-eval-disallow-images.mjs b/testing/web-platform/tests/origin-policy/content-security/resources/disallow-unsafe-eval-disallow-images.mjs
new file mode 100644
index 0000000000000..41b25553d5633
--- /dev/null
+++ b/testing/web-platform/tests/origin-policy/content-security/resources/disallow-unsafe-eval-disallow-images.mjs
@@ -0,0 +1,3 @@
+import { runCSPTest } from "./helper.mjs";
+
+runCSPTest({ unsafeEval: false, img: false });
diff --git a/testing/web-platform/tests/origin-policy/content-security/helper.js b/testing/web-platform/tests/origin-policy/content-security/resources/helper.mjs
similarity index 89%
rename from testing/web-platform/tests/origin-policy/content-security/helper.js
rename to testing/web-platform/tests/origin-policy/content-security/resources/helper.mjs
index 4875977afa443..5eff7e16ba04a 100644
--- a/testing/web-platform/tests/origin-policy/content-security/helper.js
+++ b/testing/web-platform/tests/origin-policy/content-security/resources/helper.mjs
@@ -1,4 +1,4 @@
-window.waitForOneSecurityPolicyViolationEvent = expectedBlockedURI => {
+export function waitForOneSecurityPolicyViolationEvent(expectedBlockedURI) {
   return new Promise(resolve => {
     let eventCount = 0;
     let blockedURI = null;
@@ -17,9 +17,9 @@ window.waitForOneSecurityPolicyViolationEvent = expectedBlockedURI => {
       });
     });
   });
-};
+}
 
-window.waitForImgFail = imgSrc => {
+export function waitForImgFail(imgSrc) {
   return new Promise((resolve, reject) => {
     const img = document.createElement("img");
     img.onload = () => reject(new Error("Must not load the image"));
@@ -28,10 +28,9 @@ window.waitForImgFail = imgSrc => {
     img.src = imgSrc;
     document.body.append(img);
   });
-};
+}
 
-
-window.waitForImgSuccess = imgSrc => {
+export function waitForImgSuccess(imgSrc) {
   return new Promise((resolve, reject) => {
     const img = document.createElement("img");
     img.onload = () => resolve();
@@ -40,10 +39,10 @@ window.waitForImgSuccess = imgSrc => {
     img.src = imgSrc;
     document.body.append(img);
   });
-};
+}
 
 // Both params are optional; if they are not given as booleans then we will not test that aspect.
-window.runCSPTest = ({ unsafeEval, img }) => {
+export function runCSPTest({ unsafeEval, img }) {
   if (unsafeEval === true) {
     test(() => {
       eval("window.evalAllowed = true;");
@@ -70,4 +69,4 @@ window.runCSPTest = ({ unsafeEval, img }) => {
       "img loading must be disallowed"
     );
   }
-};
+}
diff --git a/testing/web-platform/tests/origin-policy/content-security/resources/trigger-violation-report-report-only.mjs b/testing/web-platform/tests/origin-policy/content-security/resources/trigger-violation-report-report-only.mjs
new file mode 100644
index 0000000000000..9766717e309b5
--- /dev/null
+++ b/testing/web-platform/tests/origin-policy/content-security/resources/trigger-violation-report-report-only.mjs
@@ -0,0 +1,12 @@
+import { waitForOneSecurityPolicyViolationEvent, waitForImgSuccess } from "./helper.mjs";
+
+promise_test(() => {
+  const imgURL = (new URL("/common/security-features/subresource/image.py", document.location)).href;
+
+  return Promise.all([
+    waitForOneSecurityPolicyViolationEvent(imgURL).then(blockedURI => {
+      assert_equals(blockedURI, imgURL);
+    }),
+    waitForImgSuccess(imgURL)
+  ]);
+});
diff --git a/testing/web-platform/tests/origin-policy/content-security/resources/trigger-violation-report.mjs b/testing/web-platform/tests/origin-policy/content-security/resources/trigger-violation-report.mjs
new file mode 100644
index 0000000000000..319c87b0f8a67
--- /dev/null
+++ b/testing/web-platform/tests/origin-policy/content-security/resources/trigger-violation-report.mjs
@@ -0,0 +1,12 @@
+import { waitForOneSecurityPolicyViolationEvent, waitForImgFail } from "./helper.mjs";
+
+promise_test(() => {
+  const imgURL = (new URL("/common/security-features/subresource/image.py", document.location)).href;
+
+  return Promise.all([
+    waitForOneSecurityPolicyViolationEvent(imgURL).then(blockedURI => {
+      assert_equals(blockedURI, imgURL);
+    }),
+    waitForImgFail(imgURL)
+  ]);
+});
diff --git a/testing/web-platform/tests/origin-policy/content-security/trigger-violation-report-report-only.https.html b/testing/web-platform/tests/origin-policy/content-security/trigger-violation-report-report-only.https.html
index 3e5038b501dec..9eb83792852eb 100644
--- a/testing/web-platform/tests/origin-policy/content-security/trigger-violation-report-report-only.https.html
+++ b/testing/web-platform/tests/origin-policy/content-security/trigger-violation-report-report-only.https.html
@@ -3,21 +3,14 @@
 <title>CSP via origin policy must trigger a securitypolicyviolation event even when the CSP is report-only</title>
 <script src="/resources/testharness.js"></script>
 <script src="/resources/testharnessreport.js"></script>
-<script src="helper.js"></script>
+<script src="../resources/origin-policy-test-runner.js"></script>
 
-<body>
+<div id="log"></div>
 
 <script>
 "use strict";
-
-promise_test(() => {
-  const imgURL = (new URL("/common/security-features/subresource/image.py", document.location)).href;
-
-  return Promise.all([
-    waitForOneSecurityPolicyViolationEvent(imgURL).then(blockedURI => {
-      assert_equals(blockedURI, imgURL);
-    }),
-    waitForImgSuccess(imgURL)
-  ]);
+runTestsInSubframe({
+  hostname: "op7",
+  testJS: "resources/trigger-violation-report-report-only.mjs"
 });
 </script>
diff --git a/testing/web-platform/tests/origin-policy/content-security/trigger-violation-report-report-only.https.html.headers b/testing/web-platform/tests/origin-policy/content-security/trigger-violation-report-report-only.https.html.headers
deleted file mode 100644
index cb27e1500e0b4..0000000000000
--- a/testing/web-platform/tests/origin-policy/content-security/trigger-violation-report-report-only.https.html.headers
+++ /dev/null
@@ -1 +0,0 @@
-Sec-Origin-Policy: policy=policy-content-security-noimg-report-only
diff --git a/testing/web-platform/tests/origin-policy/content-security/trigger-violation-report.https.html b/testing/web-platform/tests/origin-policy/content-security/trigger-violation-report.https.html
index 22beca5a3dbbc..f981b2b05cef7 100644
--- a/testing/web-platform/tests/origin-policy/content-security/trigger-violation-report.https.html
+++ b/testing/web-platform/tests/origin-policy/content-security/trigger-violation-report.https.html
@@ -3,21 +3,14 @@
 <title>CSP via origin policy must trigger a securitypolicyviolation event</title>
 <script src="/resources/testharness.js"></script>
 <script src="/resources/testharnessreport.js"></script>
-<script src="helper.js"></script>
+<script src="../resources/origin-policy-test-runner.js"></script>
 
-<body>
+<div id="log"></div>
 
 <script>
 "use strict";
-
-promise_test(() => {
-  const imgURL = (new URL("/common/security-features/subresource/image.py", document.location)).href;
-
-  return Promise.all([
-    waitForOneSecurityPolicyViolationEvent(imgURL).then(blockedURI => {
-      assert_equals(blockedURI, imgURL);
-    }),
-    waitForImgFail(imgURL)
-  ]);
+runTestsInSubframe({
+  hostname: "op8",
+  testJS: "resources/trigger-violation-report.mjs"
 });
 </script>
diff --git a/testing/web-platform/tests/origin-policy/content-security/trigger-violation-report.https.html.headers b/testing/web-platform/tests/origin-policy/content-security/trigger-violation-report.https.html.headers
deleted file mode 100644
index 08bcb9fa94171..0000000000000
--- a/testing/web-platform/tests/origin-policy/content-security/trigger-violation-report.https.html.headers
+++ /dev/null
@@ -1 +0,0 @@
-Sec-Origin-Policy: policy=policy-content-security-noimg
diff --git a/testing/web-platform/tests/origin-policy/content-security/valid-with-multi-item-array.https.html b/testing/web-platform/tests/origin-policy/content-security/valid-with-multi-item-array.https.html
index bc9ebd0cccfcb..36333a1e4b199 100644
--- a/testing/web-platform/tests/origin-policy/content-security/valid-with-multi-item-array.https.html
+++ b/testing/web-platform/tests/origin-policy/content-security/valid-with-multi-item-array.https.html
@@ -3,11 +3,14 @@
 <title>"content_security/policy" can contain multiple array items to enforce multiple CSPs</title>
 <script src="/resources/testharness.js"></script>
 <script src="/resources/testharnessreport.js"></script>
-<script src="helper.js"></script>
+<script src="../resources/origin-policy-test-runner.js"></script>
 
-<body>
+<div id="log"></div>
 
 <script>
 "use strict";
-runCSPTest({ unsafeEval: false, img: false });
+runTestsInSubframe({
+  hostname: "op9",
+  testJS: "resources/disallow-unsafe-eval-disallow-images.mjs"
+});
 </script>
diff --git a/testing/web-platform/tests/origin-policy/content-security/valid-with-multi-item-array.https.html.headers b/testing/web-platform/tests/origin-policy/content-security/valid-with-multi-item-array.https.html.headers
deleted file mode 100644
index eeddaba7a59b5..0000000000000
--- a/testing/web-platform/tests/origin-policy/content-security/valid-with-multi-item-array.https.html.headers
+++ /dev/null
@@ -1 +0,0 @@
-Sec-Origin-Policy: policy=policy-content-security-valid-with-semicolon
diff --git a/testing/web-platform/tests/origin-policy/content-security/valid-with-semicolon.https.html b/testing/web-platform/tests/origin-policy/content-security/valid-with-semicolon.https.html
index 82158f1cf7044..9eadc8f89d31a 100644
--- a/testing/web-platform/tests/origin-policy/content-security/valid-with-semicolon.https.html
+++ b/testing/web-platform/tests/origin-policy/content-security/valid-with-semicolon.https.html
@@ -3,11 +3,14 @@
 <title>"content_security/policy" array items can contain semicolons to enforce multiple CSP directives</title>
 <script src="/resources/testharness.js"></script>
 <script src="/resources/testharnessreport.js"></script>
-<script src="helper.js"></script>
+<script src="../resources/origin-policy-test-runner.js"></script>
 
-<body>
+<div id="log"></div>
 
 <script>
 "use strict";
-runCSPTest({ unsafeEval: false, img: false });
+runTestsInSubframe({
+  hostname: "op10",
+  testJS: "resources/disallow-unsafe-eval-disallow-images.mjs"
+});
 </script>
diff --git a/testing/web-platform/tests/origin-policy/content-security/valid-with-semicolon.https.html.headers b/testing/web-platform/tests/origin-policy/content-security/valid-with-semicolon.https.html.headers
deleted file mode 100644
index eeddaba7a59b5..0000000000000
--- a/testing/web-platform/tests/origin-policy/content-security/valid-with-semicolon.https.html.headers
+++ /dev/null
@@ -1 +0,0 @@
-Sec-Origin-Policy: policy=policy-content-security-valid-with-semicolon
diff --git a/testing/web-platform/tests/origin-policy/content-security/valid.https.html b/testing/web-platform/tests/origin-policy/content-security/valid.https.html
deleted file mode 100644
index 36e5ddbf958b3..0000000000000
--- a/testing/web-platform/tests/origin-policy/content-security/valid.https.html
+++ /dev/null
@@ -1,11 +0,0 @@
-<!DOCTYPE HTML>
-<meta charset="utf-8">
-<title>Valid "content_security" member disallows eval</title>
-<script src="/resources/testharness.js"></script>
-<script src="/resources/testharnessreport.js"></script>
-<script src="helper.js"></script>
-
-<script>
-"use strict";
-runCSPTest({ unsafeEval: false });
-</script>
diff --git a/testing/web-platform/tests/origin-policy/content-security/valid.https.html.headers b/testing/web-platform/tests/origin-policy/content-security/valid.https.html.headers
deleted file mode 100644
index 78aeeacd934c9..0000000000000
--- a/testing/web-platform/tests/origin-policy/content-security/valid.https.html.headers
+++ /dev/null
@@ -1 +0,0 @@
-Sec-Origin-Policy: policy=policy-content-security-valid
diff --git a/testing/web-platform/tests/origin-policy/features/comma-in-policy.https.html b/testing/web-platform/tests/origin-policy/features/comma-in-policy.https.html
index 1b991f0d8b68a..a9faba4bfd4dd 100644
--- a/testing/web-platform/tests/origin-policy/features/comma-in-policy.https.html
+++ b/testing/web-platform/tests/origin-policy/features/comma-in-policy.https.html
@@ -3,9 +3,14 @@
 <title>Commas in "features/policy" cause parse errors and thus no feature policy</title>
 <script src="/resources/testharness.js"></script>
 <script src="/resources/testharnessreport.js"></script>
-<script src="helper.js"></script>
+<script src="../resources/origin-policy-test-runner.js"></script>
+
+<div id="log"></div>
 
 <script>
 "use strict";
-runFPTest({ camera: false, geolocation: false });
+runTestsInSubframe({
+  hostname: "op1",
+  testJS: "resources/no-camera-no-geolocation.mjs"
+});
 </script>
diff --git a/testing/web-platform/tests/origin-policy/features/comma-in-policy.https.html.headers b/testing/web-platform/tests/origin-policy/features/comma-in-policy.https.html.headers
deleted file mode 100644
index c0e68720516a6..0000000000000
--- a/testing/web-platform/tests/origin-policy/features/comma-in-policy.https.html.headers
+++ /dev/null
@@ -1 +0,0 @@
-Sec-Origin-Policy: policy=policy-features-comma-in-policy
diff --git a/testing/web-platform/tests/origin-policy/features/double-features.https.html b/testing/web-platform/tests/origin-policy/features/double-features.https.html
index 8397f849f3014..aa687d681c66d 100644
--- a/testing/web-platform/tests/origin-policy/features/double-features.https.html
+++ b/testing/web-platform/tests/origin-policy/features/double-features.https.html
@@ -3,9 +3,14 @@
 <title>Of two "features" items only the second counts</title>
 <script src="/resources/testharness.js"></script>
 <script src="/resources/testharnessreport.js"></script>
-<script src="helper.js"></script>
+<script src="../resources/origin-policy-test-runner.js"></script>
+
+<div id="log"></div>
 
 <script>
 "use strict";
-runFPTest({ camera: false, geolocation: true });
+runTestsInSubframe({
+  hostname: "op2",
+  testJS: "resources/no-camera-yes-geolocation.mjs"
+});
 </script>
diff --git a/testing/web-platform/tests/origin-policy/features/double-features.https.html.headers b/testing/web-platform/tests/origin-policy/features/double-features.https.html.headers
deleted file mode 100644
index f0a57380a8f57..0000000000000
--- a/testing/web-platform/tests/origin-policy/features/double-features.https.html.headers
+++ /dev/null
@@ -1 +0,0 @@
-Sec-Origin-Policy: policy=policy-features-double-features
diff --git a/testing/web-platform/tests/origin-policy/features/double-policy.https.html b/testing/web-platform/tests/origin-policy/features/double-policy.https.html
index f1d63d6de966b..d9e544acaaf6a 100644
--- a/testing/web-platform/tests/origin-policy/features/double-policy.https.html
+++ b/testing/web-platform/tests/origin-policy/features/double-policy.https.html
@@ -3,9 +3,14 @@
 <title>Of two "features/policy" items only the second counts</title>
 <script src="/resources/testharness.js"></script>
 <script src="/resources/testharnessreport.js"></script>
-<script src="helper.js"></script>
+<script src="../resources/origin-policy-test-runner.js"></script>
+
+<div id="log"></div>
 
 <script>
 "use strict";
-runFPTest({ camera: false, geolocation: true });
+runTestsInSubframe({
+  hostname: "op2",
+  testJS: "resources/no-camera-yes-geolocation.mjs"
+});
 </script>
diff --git a/testing/web-platform/tests/origin-policy/features/double-policy.https.html.headers b/testing/web-platform/tests/origin-policy/features/double-policy.https.html.headers
deleted file mode 100644
index c1421693e4daf..0000000000000
--- a/testing/web-platform/tests/origin-policy/features/double-policy.https.html.headers
+++ /dev/null
@@ -1 +0,0 @@
-Sec-Origin-Policy: policy=policy-features-double-policy
diff --git a/testing/web-platform/tests/origin-policy/features/non-object.https.html b/testing/web-platform/tests/origin-policy/features/non-object.https.html
index 31f632bf0f1fe..2bd4b67e600c9 100644
--- a/testing/web-platform/tests/origin-policy/features/non-object.https.html
+++ b/testing/web-platform/tests/origin-policy/features/non-object.https.html
@@ -3,9 +3,14 @@
 <title>Non-object "features" member must be ignored</title>
 <script src="/resources/testharness.js"></script>
 <script src="/resources/testharnessreport.js"></script>
-<script src="helper.js"></script>
+<script src="../resources/origin-policy-test-runner.js"></script>
+
+<div id="log"></div>
 
 <script>
 "use strict";
-runFPTest({ camera: false, geolocation: false });
+runTestsInSubframe({
+  hostname: "op5",
+  testJS: "resources/no-camera-no-geolocation.mjs"
+});
 </script>
diff --git a/testing/web-platform/tests/origin-policy/features/non-object.https.html.headers b/testing/web-platform/tests/origin-policy/features/non-object.https.html.headers
deleted file mode 100644
index e8f68712ed341..0000000000000
--- a/testing/web-platform/tests/origin-policy/features/non-object.https.html.headers
+++ /dev/null
@@ -1 +0,0 @@
-Sec-Origin-Policy: policy=policy-features-non-object
diff --git a/testing/web-platform/tests/origin-policy/features/non-string.https.html b/testing/web-platform/tests/origin-policy/features/non-string.https.html
index 019014c980a4a..190d224a4cfe0 100644
--- a/testing/web-platform/tests/origin-policy/features/non-string.https.html
+++ b/testing/web-platform/tests/origin-policy/features/non-string.https.html
@@ -3,9 +3,14 @@
 <title>Non-string "features/policy" member must be ignored</title>
 <script src="/resources/testharness.js"></script>
 <script src="/resources/testharnessreport.js"></script>
-<script src="helper.js"></script>
+<script src="../resources/origin-policy-test-runner.js"></script>
+
+<div id="log"></div>
 
 <script>
 "use strict";
-runFPTest({ camera: false, geolocation: false });
+runTestsInSubframe({
+  hostname: "op6",
+  testJS: "resources/no-camera-no-geolocation.mjs"
+});
 </script>
diff --git a/testing/web-platform/tests/origin-policy/features/non-string.https.html.headers b/testing/web-platform/tests/origin-policy/features/non-string.https.html.headers
deleted file mode 100644
index 4c6c376697b85..0000000000000
--- a/testing/web-platform/tests/origin-policy/features/non-string.https.html.headers
+++ /dev/null
@@ -1 +0,0 @@
-Sec-Origin-Policy: policy=policy-features-non-string
diff --git a/testing/web-platform/tests/origin-policy/features/helper.js b/testing/web-platform/tests/origin-policy/features/resources/helper.mjs
similarity index 83%
rename from testing/web-platform/tests/origin-policy/features/helper.js
rename to testing/web-platform/tests/origin-policy/features/resources/helper.mjs
index f9c16b58c2cf8..7ced355e645c7 100644
--- a/testing/web-platform/tests/origin-policy/features/helper.js
+++ b/testing/web-platform/tests/origin-policy/features/resources/helper.mjs
@@ -1,8 +1,8 @@
 "use strict";
 
-window.runFPTest = ({ camera, geolocation }) => {
+export function runFPTest({ camera, geolocation }) {
   test(() => {
     assert_equals(document.featurePolicy.allowsFeature('camera', 'https://example.com/'), camera, 'camera');
     assert_equals(document.featurePolicy.allowsFeature('geolocation', 'https://example.com/'), geolocation, 'geolocation');
   });
-};
+}
diff --git a/testing/web-platform/tests/origin-policy/features/resources/no-camera-no-geolocation.mjs b/testing/web-platform/tests/origin-policy/features/resources/no-camera-no-geolocation.mjs
new file mode 100644
index 0000000000000..b25d9abcb92ec
--- /dev/null
+++ b/testing/web-platform/tests/origin-policy/features/resources/no-camera-no-geolocation.mjs
@@ -0,0 +1,3 @@
+import { runFPTest } from "./helper.mjs";
+
+runFPTest({ camera: false, geolocation: false });
diff --git a/testing/web-platform/tests/origin-policy/features/resources/no-camera-yes-geolocation.mjs b/testing/web-platform/tests/origin-policy/features/resources/no-camera-yes-geolocation.mjs
new file mode 100644
index 0000000000000..a961deeb38989
--- /dev/null
+++ b/testing/web-platform/tests/origin-policy/features/resources/no-camera-yes-geolocation.mjs
@@ -0,0 +1,3 @@
+import { runFPTest } from "./helper.mjs";
+
+runFPTest({ camera: false, geolocation: true });
diff --git a/testing/web-platform/tests/origin-policy/features/resources/yes-camera-yes-geolocation.mjs b/testing/web-platform/tests/origin-policy/features/resources/yes-camera-yes-geolocation.mjs
new file mode 100644
index 0000000000000..9f3b1d8303fe6
--- /dev/null
+++ b/testing/web-platform/tests/origin-policy/features/resources/yes-camera-yes-geolocation.mjs
@@ -0,0 +1,3 @@
+import { runFPTest } from "./helper.mjs";
+
+runFPTest({ camera: true, geolocation: true });
diff --git a/testing/web-platform/tests/origin-policy/features/valid-with-semicolon.https.html b/testing/web-platform/tests/origin-policy/features/valid-with-semicolon.https.html
new file mode 100644
index 0000000000000..8d2d0f4495ff7
--- /dev/null
+++ b/testing/web-platform/tests/origin-policy/features/valid-with-semicolon.https.html
@@ -0,0 +1,16 @@
+<!DOCTYPE HTML>
+<meta charset="utf-8">
+<title>Valid "features" member, with a semicolon</title>
+<script src="/resources/testharness.js"></script>
+<script src="/resources/testharnessreport.js"></script>
+<script src="../resources/origin-policy-test-runner.js"></script>
+
+<div id="log"></div>
+
+<script>
+"use strict";
+runTestsInSubframe({
+  hostname: "op10",
+  testJS: "resources/yes-camera-yes-geolocation.mjs"
+});
+</script>
diff --git a/testing/web-platform/tests/origin-policy/features/valid.https.html b/testing/web-platform/tests/origin-policy/features/valid.https.html
deleted file mode 100644
index 6ff2076a7f076..0000000000000
--- a/testing/web-platform/tests/origin-policy/features/valid.https.html
+++ /dev/null
@@ -1,11 +0,0 @@
-<!DOCTYPE HTML>
-<meta charset="utf-8">
-<title>Valid "features" member</title>
-<script src="/resources/testharness.js"></script>
-<script src="/resources/testharnessreport.js"></script>
-<script src="helper.js"></script>
-
-<script>
-"use strict";
-runFPTest({ camera: true, geolocation: true });
-</script>
diff --git a/testing/web-platform/tests/origin-policy/features/valid.https.html.headers b/testing/web-platform/tests/origin-policy/features/valid.https.html.headers
deleted file mode 100644
index 9d0e25792c46d..0000000000000
--- a/testing/web-platform/tests/origin-policy/features/valid.https.html.headers
+++ /dev/null
@@ -1 +0,0 @@
-Sec-Origin-Policy: policy=policy-features-valid
diff --git a/testing/web-platform/tests/origin-policy/origin-policy-report-to.https.tentative.sub.html b/testing/web-platform/tests/origin-policy/origin-policy-report-to.https.tentative.sub.html
deleted file mode 100644
index dfef7a1d133c2..0000000000000
--- a/testing/web-platform/tests/origin-policy/origin-policy-report-to.https.tentative.sub.html
+++ /dev/null
@@ -1,22 +0,0 @@
-<!DOCTYPE HTML>
-<html>
-<head>
-  <title>Test that Origin Policy report-to are deliverd to the declared reporting group</title>
-  <script src='/resources/testharness.js'></script>
-  <script src='/resources/testharnessreport.js'></script>
-</head>
-<body>
-  <iframe id="frame" src="about:blank"></iframe>
-  <script>
-    // Navigate the frame to a URL that declares an (invalid) origin policy with
-    // a report-to directive.
-    document.getElementById("frame").src =
-        "https://{{hosts[alt][]}}:{{ports[https][0]}}/origin-policy/sec-origin-policy-subframe.html";
-  </script>
-  <script async defer src='/content-security-policy/support/checkReport.sub.js?reportField=policy&reportValue=nonexistingpolicy'>
-    // This re-uses CSP reporting test infrastructure, and contains the actual
-    // test. In addition to sanity checks, it will check whether the report body
-    // contains a key/value pair as indicated by reportField and reportValue.
-  </script>
-</body>
-</html>
diff --git a/testing/web-platform/tests/origin-policy/origin-policy-report-to.https.tentative.sub.html.sub.headers b/testing/web-platform/tests/origin-policy/origin-policy-report-to.https.tentative.sub.html.sub.headers
deleted file mode 100644
index 92a90c347d3a7..0000000000000
--- a/testing/web-platform/tests/origin-policy/origin-policy-report-to.https.tentative.sub.html.sub.headers
+++ /dev/null
@@ -1 +0,0 @@
-Set-Cookie: origin-policy-report-to=5b4d35b6-0771-46fe-8700-ed2bb59ed4be; Path=/origin-policy/
diff --git a/testing/web-platform/tests/origin-policy/origin-policy.https.tentative.html b/testing/web-platform/tests/origin-policy/origin-policy.https.tentative.html
deleted file mode 100644
index 34a71fe40a192..0000000000000
--- a/testing/web-platform/tests/origin-policy/origin-policy.https.tentative.html
+++ /dev/null
@@ -1,143 +0,0 @@
-<!DOCTYPE HTML>
-<html>
-<head>
-  <script src='/resources/testharness.js'></script>
-  <script src='/resources/testharnessreport.js'></script>
-</head>
-<body>
-  <div id=log></div>
-  <iframe id=frame></iframe>
-  <script>
-    // Navigate the frame to a test page with the given policy and wait for
-    // postMessage to arrive. Resolve the result promise with the message.
-    function navigate(policy) {
-      return new Promise(resolve => {
-        window.addEventListener("message", event => { resolve(event.data); },
-                                { once: true });
-        document.getElementById("frame").src =
-            "/origin-policy/sec-origin-policy-header.html.py?policy=" + policy;
-      });
-    }
-
-    // Check whether the message returned from the frame meets our expectations.
-    function expect(expect_script, expect_eval, message) {
-      assert_own_property(message, "inline_allowed");
-      assert_own_property(message, "eval_allowed");
-      assert_equals(message.inline_allowed, expect_script);
-      assert_equals(message.eval_allowed, expect_eval);
-    }
-
-    // Generate a more descriptive error message. Re-throw the error.
-    function descriptive_message(policy, expect_inline, expect_eval,
-                                 index, error) {
-      error.message = `Error occured on entry #${index + 1} ["${policy
-          }", ${expect_inline}, ${expect_eval}]: "${error}".`;
-      throw(error);
-    }
-
-    // Run the navigation + expectation checking for one test case line.
-    function test_case_entry([policy, expect_inline, expect_eval], index) {
-      return navigate(policy)
-          .then(message => expect(expect_inline, expect_eval, message))
-
-          // This catch handler merely logs a more friendly message,
-          // pointing you to the exact line of the failing test.
-          .catch(error => descriptive_message(policy, expect_inline,
-                                              expect_eval, index, error));
-    }
-
-    function origin_policy_csp_test_case(test_case_list) {
-      return t => {
-        // Setup the promise chain for the test.
-        let chain = Promise.resolve();
-        for ([index, val] of test_case_list.entries())
-          chain = chain.then(test_case_entry.bind(this, val, index));
-
-        // Delete the policy as the last element of the chain, on both
-        // resolve + reject paths, so that a left-over policy won't break
-        // subsequent tests.
-        return chain.then(() => navigate("0"),
-                          (error) => { navigate("0"); throw error; });
-      }
-    }
-
-
-    // Sanity check: A request with no policy.
-    promise_test(origin_policy_csp_test_case([
-        ["", true, true],  // No policy.
-    ]), "sanity check");
-
-    // Basic functionality. A policy should have an effect.
-    promise_test(origin_policy_csp_test_case([
-        ["",             true, true],  // No policy.
-        ["policy-csp-1", true, false], // policy-csp-1, which forbids eval.
-        ["0",            true, true],  // Delete the policy again.
-      ]), "The basics: A policy should have an effect..");
-
-    // Basic functionality. Set a policy. Make sure it "sticks".
-    promise_test(origin_policy_csp_test_case([
-        ["",             true, true],  // No policy.
-        ["policy-csp-1", true, false], // policy-csp-1, which forbids eval.
-        ["",             true, false], // No policy. Should remember p...-csp-1.
-        ["0",            true, true],  // Delete the policy again.
-      ]), "The basics: A policy should stick.");
-
-    // Set, update, and delete a policy.
-    promise_test(origin_policy_csp_test_case([
-        ["",             true,  true],
-        ["policy-csp-1", true,  false], // policy-csp-1, which forbids eval.
-        ["policy-csp-2", false, false], // policy-csp-2, forbids script + eval.
-        ["0",            true,  true],  // Delete the policy.
-      ]), "Policy set, update, and delete.");
-
-    // Set, update, and delete a policy. Check on each step whether it 'sticks'.
-    promise_test(origin_policy_csp_test_case([
-        ["",             true,  true],
-        ["policy-csp-1", true,  false], // policy-csp-1, which forbids eval.
-        ["",             true,  false],
-        ["policy-csp-2", false, false], // Forbid script + eval.
-        ["",             false, false],
-        ["0",            true,  true],  // Delete the policy.
-        ["",             true,  true],
-      ]), "Policy set-update-delete cycle with checks.");
-
-    // Set a policy, update, then revert to the old one.
-    promise_test(origin_policy_csp_test_case([
-        ["",             true,  true],
-        ["policy-csp-1", true,  false], // policy-csp-1, which forbids eval.
-        ["policy-csp-2", false, false], // Forbid script + eval.
-        ["policy-csp-1", true,  false], // policy-csp-1 again.
-        ["0",            true,  true],
-      ]), "Policy set-update-delete cycle.");
-
-    // Set, delete, re-set, and re-delete a policy.
-    promise_test(origin_policy_csp_test_case([
-        ["",             true, true],  // No policy.
-        ["policy-csp-1", true, false], // policy-csp-1, which forbids eval.
-        ["",             true, false],
-        ["0",            true, true],  // Delete the policy.
-        ["",             true, true],
-        ["policy-csp-1", true, false], // Set policy after policy was deleted.
-        ["",             true, false],
-        ["0",            true, true],  // Delete the policy again.
-        ["",             true, true],
-      ]), "Policy re-set and re-delete.");
-
-    // We've had some bugs with repeated policies being set, so lets just
-    // run through a set-update-delete cycle but with every request being
-    // made twice.
-    promise_test(origin_policy_csp_test_case([
-        ["",             true,  true],
-        ["",             true,  true],
-        ["policy-csp-1", true,  false],
-        ["policy-csp-1", true,  false],
-        ["policy-csp-2", false, false],
-        ["policy-csp-2", false, false],
-        ["0",            true,  true],
-        ["0",            true,  true],
-        ["",             true,  true],
-        ["",             true,  true],
-      ]), "Double Trouble");
-  </script>
-</body>
-</html>
diff --git a/testing/web-platform/tests/origin-policy/policies/README.md b/testing/web-platform/tests/origin-policy/policies/README.md
new file mode 100644
index 0000000000000..b07be74035f2d
--- /dev/null
+++ b/testing/web-platform/tests/origin-policy/policies/README.md
@@ -0,0 +1,5 @@
+These policies are served via the Python script at /.well-known/origin-policy. Their filenames must be in the form `subdomain human-facing-string-with-no-spaces.json`. They will be served in response to requests to that subdomain.
+
+The human-facing string has no impact on the tests, and just makes it easier to scroll through the list.
+
+The list of potential hostnames is created by `tools/serve/serve.py`'s `_make_origin_policy_subdomains` function, and can be expanded as necessary.
diff --git a/testing/web-platform/tests/origin-policy/policies/op1 cspfp-comma-in-policy.json b/testing/web-platform/tests/origin-policy/policies/op1 cspfp-comma-in-policy.json
new file mode 100644
index 0000000000000..189d28db8ba80
--- /dev/null
+++ b/testing/web-platform/tests/origin-policy/policies/op1 cspfp-comma-in-policy.json	
@@ -0,0 +1,13 @@
+{
+  "ids": [
+    "cspfp-comma-in-policy"
+  ],
+  "content_security": {
+    "policies": [
+      "script-src 'self' 'unsafe-inline', img-src 'none'"
+    ]
+  },
+  "features": {
+    "policy": "camera 'self' https://example.com/, geolocation 'self' https://example.com/"
+  }
+}
diff --git a/testing/web-platform/tests/origin-policy/policies/op10 cspfp-valid.json b/testing/web-platform/tests/origin-policy/policies/op10 cspfp-valid.json
new file mode 100644
index 0000000000000..0fc1d163f2b61
--- /dev/null
+++ b/testing/web-platform/tests/origin-policy/policies/op10 cspfp-valid.json	
@@ -0,0 +1,13 @@
+{
+  "ids": [
+    "cspfp-valid"
+  ],
+  "content_security": {
+    "policies": [
+      "script-src 'self' 'unsafe-inline'; img-src 'none'"
+    ]
+  },
+  "features": {
+    "policy": "camera 'self' https://example.com/; geolocation 'self' https://example.com/"
+  }
+}
diff --git a/testing/web-platform/tests/origin-policy/policies/op2 cspfp-double-top-level.json b/testing/web-platform/tests/origin-policy/policies/op2 cspfp-double-top-level.json
new file mode 100644
index 0000000000000..26d798b585d96
--- /dev/null
+++ b/testing/web-platform/tests/origin-policy/policies/op2 cspfp-double-top-level.json	
@@ -0,0 +1,21 @@
+{
+  "ids": [
+    "cspfp-double-top-level"
+  ],
+  "content_security": {
+    "policies": [
+      "script-src 'self' 'unsafe-inline'"
+    ]
+  },
+  "content_security": {
+    "policies": [
+      "img-src 'none'"
+    ]
+  },
+  "features": {
+    "policy": "camera 'self' https://example.com/"
+  },
+  "features": {
+    "policy": "geolocation 'self' https://example.com/"
+  }
+}
diff --git a/testing/web-platform/tests/origin-policy/policies/op3 cspfp-double-second-level.json b/testing/web-platform/tests/origin-policy/policies/op3 cspfp-double-second-level.json
new file mode 100644
index 0000000000000..6665332807bea
--- /dev/null
+++ b/testing/web-platform/tests/origin-policy/policies/op3 cspfp-double-second-level.json	
@@ -0,0 +1,17 @@
+{
+  "ids": [
+    "cspfp-double-second-level"
+  ],
+  "content_security": {
+    "policies": [
+      "script-src 'self' 'unsafe-inline'"
+    ],
+    "policies": [
+      "img-src 'none'"
+    ]
+  },
+  "features": {
+    "policy": "camera 'self' https://example.com/",
+    "policy": "geolocation 'self' https://example.com/"
+  }
+}
diff --git a/testing/web-platform/tests/.well-known/origin-policy/policy-content-security-non-array b/testing/web-platform/tests/origin-policy/policies/op4 csp-non-array.json
similarity index 70%
rename from testing/web-platform/tests/.well-known/origin-policy/policy-content-security-non-array
rename to testing/web-platform/tests/origin-policy/policies/op4 csp-non-array.json
index b96546c5f88fe..5916b1ff9b572 100644
--- a/testing/web-platform/tests/.well-known/origin-policy/policy-content-security-non-array
+++ b/testing/web-platform/tests/origin-policy/policies/op4 csp-non-array.json	
@@ -1,4 +1,7 @@
 {
+  "ids": [
+    "csp-non-array"
+  ],
   "content_security": {
     "policies": "script-src 'self' 'unsafe-inline'"
   }
diff --git a/testing/web-platform/tests/origin-policy/policies/op5 cspfp-non-object.json b/testing/web-platform/tests/origin-policy/policies/op5 cspfp-non-object.json
new file mode 100644
index 0000000000000..7488f9bfef297
--- /dev/null
+++ b/testing/web-platform/tests/origin-policy/policies/op5 cspfp-non-object.json	
@@ -0,0 +1,9 @@
+{
+  "ids": [
+    "cspfp-non-object"
+  ],
+  "content_security": [
+    "script-src 'self' 'unsafe-inline'"
+  ],
+  "features": "camera 'self' https://example.com/"
+}
diff --git a/testing/web-platform/tests/origin-policy/policies/op6 cspfp-non-string.json b/testing/web-platform/tests/origin-policy/policies/op6 cspfp-non-string.json
new file mode 100644
index 0000000000000..5c6941bf8fd18
--- /dev/null
+++ b/testing/web-platform/tests/origin-policy/policies/op6 cspfp-non-string.json	
@@ -0,0 +1,17 @@
+{
+  "ids": [
+    "csp-non-string"
+  ],
+  "content_security": {
+    "policies": [
+      [
+        "script-src 'self' 'unsafe-inline'"
+      ]
+    ]
+  },
+  "features": {
+    "policy": [
+      "camera 'self' https://example.com/"
+    ]
+  }
+}
diff --git a/testing/web-platform/tests/origin-policy/policies/op7 csp-noimg-report-only.json b/testing/web-platform/tests/origin-policy/policies/op7 csp-noimg-report-only.json
new file mode 100644
index 0000000000000..fd5c522042a7e
--- /dev/null
+++ b/testing/web-platform/tests/origin-policy/policies/op7 csp-noimg-report-only.json	
@@ -0,0 +1,10 @@
+{
+  "ids": [
+    "csp-noimg-report-only"
+  ],
+  "content_security": {
+    "policies_report_only": [
+      "img-src 'none'"
+    ]
+  }
+}
diff --git a/testing/web-platform/tests/.well-known/origin-policy/policy-content-security-noimg b/testing/web-platform/tests/origin-policy/policies/op8 csp-noimg.json
similarity index 67%
rename from testing/web-platform/tests/.well-known/origin-policy/policy-content-security-noimg
rename to testing/web-platform/tests/origin-policy/policies/op8 csp-noimg.json
index cd57b7b21e916..b88e1f80bf93c 100644
--- a/testing/web-platform/tests/.well-known/origin-policy/policy-content-security-noimg
+++ b/testing/web-platform/tests/origin-policy/policies/op8 csp-noimg.json	
@@ -1,4 +1,7 @@
 {
+  "ids": [
+    "csp-noimg"
+  ],
   "content_security": {
     "policies": ["img-src 'none'"]
   }
diff --git a/testing/web-platform/tests/origin-policy/policies/op9 csp-valid-with-multi-item-array.json b/testing/web-platform/tests/origin-policy/policies/op9 csp-valid-with-multi-item-array.json
new file mode 100644
index 0000000000000..edd743038db8d
--- /dev/null
+++ b/testing/web-platform/tests/origin-policy/policies/op9 csp-valid-with-multi-item-array.json	
@@ -0,0 +1,11 @@
+{
+  "ids": [
+    "csp-valid-with-multi-item-array"
+  ],
+  "content_security": {
+    "policies": [
+      "script-src 'self' 'unsafe-inline'",
+      "img-src 'none'"
+    ]
+  }
+}
diff --git a/testing/web-platform/tests/origin-policy/resources/origin-policy-test-runner.js b/testing/web-platform/tests/origin-policy/resources/origin-policy-test-runner.js
new file mode 100644
index 0000000000000..a1c6453debd20
--- /dev/null
+++ b/testing/web-platform/tests/origin-policy/resources/origin-policy-test-runner.js
@@ -0,0 +1,28 @@
+window.runTestsInSubframe = ({ hostname, testJS }) => {
+  test(() => {
+    assert_equals(location.protocol, "https:");
+  }, "Prerequisite check: running on HTTPS");
+
+  promise_test(() => new Promise((resolve, reject) => {
+    const url = new URL(window.location.href);
+    url.hostname = `${hostname}.${document.domain}`;
+    url.pathname = "/origin-policy/resources/subframe-with-origin-policy.py";
+
+    // Normalize the URL so that callers can idiomatically give values relative
+    // to themselves.
+    url.searchParams.append("test", new URL(testJS, document.baseURI).pathname);
+
+    const iframe = document.createElement("iframe");
+    iframe.src = url.href;
+
+    // We need to delegate anything we plan to toggle with FP otherwise it will
+    // be locked to disallowed.
+    iframe.allow = "camera *; geolocation *";
+
+    iframe.onload = resolve;
+    iframe.onerror = () => reject(new Error(`Could not load ${url.href}`));
+    document.body.append(iframe);
+
+    fetch_tests_from_window(iframe.contentWindow);
+  }), "Test setup of the iframe");
+};
diff --git a/testing/web-platform/tests/origin-policy/resources/subframe-with-origin-policy.py b/testing/web-platform/tests/origin-policy/resources/subframe-with-origin-policy.py
new file mode 100644
index 0000000000000..636a649a0e20b
--- /dev/null
+++ b/testing/web-platform/tests/origin-policy/resources/subframe-with-origin-policy.py
@@ -0,0 +1,26 @@
+def main(request, response):
+    """Send a response with the Origin-Policy header asking for the latest
+      policy, that runs the test JS given by the ?test= argument. This is meant
+       to be loaded into an iframe by origin-policy-test-runner.js.
+
+       The ?test= argument is best given as an absolute path (starting with /)
+       since it will otherwise be interpreted relative to where this file is
+       served.
+    """
+    test_file = request.GET.first("test")
+
+    response.headers.set("Origin-Policy", "allowed=(latest)")
+    response.headers.set("Content-Type", "text/html")
+
+    return """
+    <!DOCTYPE html>
+    <meta charset="utf-8">
+    <title>Origin policy subframe</title>
+
+    <script src="/resources/testharness.js"></script>
+    <script src="/resources/testharnessreport.js"></script>
+
+    <div id="log"></div>
+
+    <script type="module" src="%s"></script>
+  """ % test_file
diff --git a/testing/web-platform/tests/origin-policy/sec-origin-policy-header.html.py b/testing/web-platform/tests/origin-policy/sec-origin-policy-header.html.py
deleted file mode 100644
index 7754e04a313c1..0000000000000
--- a/testing/web-platform/tests/origin-policy/sec-origin-policy-header.html.py
+++ /dev/null
@@ -1,64 +0,0 @@
-def main(request, response):
-  """Send a response with the origin policy indicated by the ?policy= argument.
-
-     Won't send a policy when the browser doesn't indicate support.
-     The response tests whether inline script and eval are allowed, and will
-     send a corresponding message to the parent frame.
-     For easier debugging, we'll also show the results in-page.
-  """
-  origin_policy_header = "Sec-Origin-Policy"
-  request_policy = request.headers.get(origin_policy_header)
-  response_policy = request.GET.first("policy", default="")
-
-  if request_policy and response_policy:
-    response.headers.set(origin_policy_header, "policy=%s" % response_policy)
-    response.headers.set("Vary", "sec-origin-policy")
-
-  response.headers.set("Content-Type", "text/html");
-  return """
-    <html>
-    <head>
-     <title>Page with an Origin Policy</title>
-    </head>
-    <body>
-    <script nonce=test>
-      let inlineAllowed = false;
-      let evalAllowed = false;
-      try { eval('evalAllowed = true;'); } catch (e) {};
-    </script>
-    <script>
-      inlineAllowed = true;
-    </script>
-
-    <p>Reveal whether CSP with "unsafe-inline" or "unsafe-eval" is present:</p>
-    <ul>
-      <li>inline script allowed: <span id=inline_allowed></span></li>
-      <li>eval allowed: <span id=eval_allowed></span></li>
-    </ul>
-
-    <script nonce=test>
-      const result = {
-        "inline_allowed": inlineAllowed,
-        "eval_allowed": evalAllowed,
-      };
-
-      // Mirror content into the page for easy debugging:
-      const styles = {
-        true: "font-weight: bold; color: green;",
-        false: "font-weight: bold; color: red",
-      }
-      for (const [key, value] of Object.entries(result)) {
-        let element = document.getElementById(key);
-        element.textContent = value.toString();
-        element.style = styles[value];
-      }
-
-      // Send result to parent frame for evaluation.
-      if (window.parent) {
-        window.parent.postMessage(result, "*");
-      }
-    </script>
-    </body>
-    </html>
-  """
-
diff --git a/testing/web-platform/tests/origin-policy/sec-origin-policy-subframe.html b/testing/web-platform/tests/origin-policy/sec-origin-policy-subframe.html
deleted file mode 100644
index d716ba11d97ce..0000000000000
--- a/testing/web-platform/tests/origin-policy/sec-origin-policy-subframe.html
+++ /dev/null
@@ -1,3 +0,0 @@
-The forbidden frame.
-Content shouldn't matter, because this frame shouldn't be loaded.
-So there.
diff --git a/testing/web-platform/tests/origin-policy/sec-origin-policy-subframe.html.sub.headers b/testing/web-platform/tests/origin-policy/sec-origin-policy-subframe.html.sub.headers
deleted file mode 100644
index a046f0096ba1b..0000000000000
--- a/testing/web-platform/tests/origin-policy/sec-origin-policy-subframe.html.sub.headers
+++ /dev/null
@@ -1,3 +0,0 @@
-Report-To: { "group": "report-to-group", "max_age": 1000, "endpoints": [{ "url": "https://{{hosts[alt][]}}:{{ports[https][0]}}/content-security-policy/support/report.py?op=put&reportID=5b4d35b6-0771-46fe-8700-ed2bb59ed4be" }] }
-Sec-Origin-Policy: policy=nonexistingpolicy, report-to=report-to-group
-