diff --git a/bun.lock b/bun.lock
index 01a19c7c..fb485882 100644
--- a/bun.lock
+++ b/bun.lock
@@ -342,7 +342,7 @@
     },
     "packages/csr": {
       "name": "@wrnexus/csr",
-      "version": "0.8.33",
+      "version": "0.8.34",
       "dependencies": {
         "@wrnexus/core": "workspace:*",
       },
@@ -688,7 +688,7 @@
     },
     "packages/ui": {
       "name": "@wrnexus/ui",
-      "version": "0.8.29",
+      "version": "0.8.30",
       "dependencies": {
         "@wrnexus/core": "workspace:*",
       },
diff --git a/docs/ui-visual-contract-0.8.json b/docs/ui-visual-contract-0.8.json
index 17519a3b..514c4dc5 100644
--- a/docs/ui-visual-contract-0.8.json
+++ b/docs/ui-visual-contract-0.8.json
@@ -55,12 +55,12 @@
     "packages/ui/components/Map.wrn": "3e6d5de5a21dd050c5c65950d6fb2f89af4024e1856a48f055b65b88fcd7b890",
     "packages/ui/components/MarketingSectionHeader.wrn": "39b79499b77dc1c7d34e4e5ecb45a9ddc6182f78c2a2586671c4fa07f44679ad",
     "packages/ui/components/Marquee.wrn": "81cd80732be34c8d7e4bf28b00347e1a9273166afdf66589d9f5d5774b69403b",
-    "packages/ui/components/MegaMenu.wrn": "ab065c8e837da5cb69f70f095a2dbed7fc0170f7ae10e758299464b1bf3b6350",
+    "packages/ui/components/MegaMenu.wrn": "c86a18489b5316047466b54a7c0b439e1b56539ab446ac88eb413a0d2c33781b",
     "packages/ui/components/MetricCard.wrn": "513a6e99be3d9db46d96af9942b51331a0a048b184603e77e814506f0a52bdc5",
     "packages/ui/components/MetricGrid.wrn": "1fcebf51dcbe8520fe16bda904c1ef206c25c3900438d53877492c64ea21a1a5",
     "packages/ui/components/Modal.wrn": "7fa4b877772736f29f690e24d8742922b310397ef3083f0b78acb67a9f0d14b2",
     "packages/ui/components/Nav.wrn": "c45b0ecb42250f4b3ede33c8932a025f789dda9ef48dbf332459ae458163e69a",
-    "packages/ui/components/Navbar.wrn": "e8f6a6367d2fe4086dc1f0fbbadc49828470a3c78ad27e30220368a5682392e5",
+    "packages/ui/components/Navbar.wrn": "cf956970f9b239d0cd2ff1e74554e07c74712a3514b2aa427352a73e5db02882",
     "packages/ui/components/PageHeader.wrn": "321cde36ce8d521a57901033d46e8b437f42e558cca27f49ca26f7172aff1d54",
     "packages/ui/components/Pagination.wrn": "d54226705d4556f76ee5f0d6ae82d101ca6d006397756d547a9aa5954415ba39",
     "packages/ui/components/PinInput.wrn": "4dc398456f6392d7925db941debb484c7cb0358ecef527f696fe5ec4800a7602",
diff --git a/packages/csr/package.json b/packages/csr/package.json
index bb288d49..95505b29 100644
--- a/packages/csr/package.json
+++ b/packages/csr/package.json
@@ -1,6 +1,6 @@
 {
   "name": "@wrnexus/csr",
-  "version": "0.8.33",
+  "version": "0.8.34",
   "type": "module",
   "main": "src/index.ts",
   "exports": {
diff --git a/packages/csr/src/index.ts b/packages/csr/src/index.ts
index 47e85ac6..6bae3639 100644
--- a/packages/csr/src/index.ts
+++ b/packages/csr/src/index.ts
@@ -90,7 +90,7 @@ const CONTROLLER_LOADER = String.raw`
     if (!componentControllerPromise) {
       componentControllerPromise = new Promise(function (resolve, reject) {
         var script = document.createElement("script");
-        script.src = componentControllerUrl;
+        script.src = trustedScriptURL(componentControllerUrl);
         script.defer = true;
         script.onload = resolve;
         script.onerror = reject;
diff --git a/packages/csr/src/reactive-runtime.ts b/packages/csr/src/reactive-runtime.ts
index 47cfd755..be91445b 100644
--- a/packages/csr/src/reactive-runtime.ts
+++ b/packages/csr/src/reactive-runtime.ts
@@ -26,6 +26,40 @@ export const REACTIVE_RUNTIME = String.raw`
   var behaviorObserver;
   var clientModuleCache = new Map();
 
+  /*
+   * Production enables require-trusted-types-for 'script'. Every HTML write
+   * below uses compiler-emitted template markup (or the explicit data-html
+   * escape hatch), and controller URLs are generated by the framework. Route
+   * those known sinks through the policy allowed by the default security
+   * preset instead of letting the browser reject hydration midway through a
+   * state update.
+   */
+  var wrnexusTrustedTypesPolicy = null;
+  if (window.trustedTypes && typeof window.trustedTypes.createPolicy === "function") {
+    try {
+      wrnexusTrustedTypesPolicy = window.trustedTypes.createPolicy("wrnexus", {
+        createHTML: function (value) { return value; },
+        createScriptURL: function (value) { return value; }
+      });
+    } catch (_) {
+      wrnexusTrustedTypesPolicy = window.trustedTypes.defaultPolicy || null;
+    }
+  }
+
+  function trustedHTML(value) {
+    var source = value == null ? "" : String(value);
+    return wrnexusTrustedTypesPolicy
+      ? wrnexusTrustedTypesPolicy.createHTML(source)
+      : source;
+  }
+
+  function trustedScriptURL(value) {
+    var source = value == null ? "" : String(value);
+    return wrnexusTrustedTypesPolicy
+      ? wrnexusTrustedTypesPolicy.createScriptURL(source)
+      : source;
+  }
+
   /*
    * Two builtin chains the runtime reaches for constantly. Aliasing them is
    * not only shorter: hasOwn keeps prototype keys from reading as data, and
@@ -1818,7 +1852,7 @@ export const REACTIVE_RUNTIME = String.raw`
                 var next = markup == null ? "" : String(markup);
 
                 if (htmlNode.innerHTML !== next) {
-                  htmlNode.innerHTML = next;
+                  htmlNode.innerHTML = trustedHTML(next);
                 }
               });
               runHtml();
@@ -2002,7 +2036,7 @@ export const REACTIVE_RUNTIME = String.raw`
       }
 
       function clearControlContent() {
-        if (!rangeEnd) { block.innerHTML = ""; return; }
+        if (!rangeEnd) { block.innerHTML = trustedHTML(""); return; }
         while (block.nextSibling && block.nextSibling !== rangeEnd) {
           block.parentNode.removeChild(block.nextSibling);
         }
@@ -2010,7 +2044,7 @@ export const REACTIVE_RUNTIME = String.raw`
 
       function appendControlContent(markup, locals) {
         var template = document.createElement("template");
-        template.innerHTML = markup || "";
+        template.innerHTML = trustedHTML(markup || "");
         var fragment = template.content;
         var elements = toArray(fragment.childNodes).filter(function (node) {
           return node.nodeType === 1;
@@ -2399,7 +2433,7 @@ export const REACTIVE_RUNTIME = String.raw`
         var markup = value == null ? "" : String(value);
 
         if (node.innerHTML !== markup) {
-          node.innerHTML = markup;
+          node.innerHTML = trustedHTML(markup);
         }
       });
     });
diff --git a/packages/csr/test/reactive.test.ts b/packages/csr/test/reactive.test.ts
index 5bce4043..12212f3c 100644
--- a/packages/csr/test/reactive.test.ts
+++ b/packages/csr/test/reactive.test.ts
@@ -62,6 +62,13 @@ test("split runtime hydrates a controller only from the controller asset", () =>
   expect(win.document.activeElement).toBe(buttons[1]);
 });
 
+test("production hydration uses Trusted Types for HTML and controller URLs", () => {
+  const runtime = getReactiveRuntime();
+  expect(runtime).toContain('createPolicy("wrnexus"');
+  expect(runtime).toContain('template.innerHTML = trustedHTML(markup || "")');
+  expect(runtime).toContain("script.src = trustedScriptURL(componentControllerUrl)");
+});
+
 test("a page without controller markers does not request the controller asset", () => {
   const win = mount(
     `<main data-scope="count: 1"><span>{count}</span></main>`,
diff --git a/packages/ui/COMPONENTS.md b/packages/ui/COMPONENTS.md
index 4f9d3b98..d2e32dac 100644
--- a/packages/ui/COMPONENTS.md
+++ b/packages/ui/COMPONENTS.md
@@ -808,7 +808,7 @@ Show responsive hierarchical navigation with home support, separators, current-p
 Theme-aware, responsive mega menu component.
 
 - Mount: `data-component="MegaMenu"`
-- Props: `color: string = "primary"`, `size: string = "default"`, `label: string = "Menu"`, `icon: string = ""`, `columns: unknown[] = []`, `rail: unknown[] = []`, `featured: Record<string, unknown> = {}`, `variant: string = "default"`, `density: string = "default"`, `panelWidth: string = "xl"`, `panelAlign: string = "start"`, `columnCount: number = 0`, `fullWidth: boolean = false`, `actionLabel: string = ""`, `actionHref: string = ""`, `actionIcon: string = "icon-[lucide--arrow-right]"`, `footer: string = ""`, `defaultOpen: boolean = false`, `class: string = ""`
+- Props: `color: string = "primary"`, `size: string = "default"`, `label: string = "Menu"`, `icon: string = ""`, `columns: unknown[] = []`, `rail: unknown[] = []`, `featured: Record<string, unknown> = {}`, `variant: string = "default"`, `density: string = "default"`, `panelWidth: string = "xl"`, `panelAlign: string = "start"`, `columnCount: number = 0`, `fullWidth: boolean = false`, `openOnHover: boolean = true`, `actionLabel: string = ""`, `actionHref: string = ""`, `actionIcon: string = "icon-[lucide--arrow-right]"`, `footer: string = ""`, `defaultOpen: boolean = false`, `class: string = ""`
 - Slots: `default`
 - Outputs: `open({ sourceEvent: Event })`, `close({ reason: string })`, `select({ item: object; value: string })`
 
diff --git a/packages/ui/component-reference.json b/packages/ui/component-reference.json
index f887e27c..e6d14bbc 100644
--- a/packages/ui/component-reference.json
+++ b/packages/ui/component-reference.json
@@ -8401,6 +8401,13 @@
           "default": "false",
           "options": []
         },
+        {
+          "name": "openOnHover",
+          "type": "boolean",
+          "required": false,
+          "default": "true",
+          "options": []
+        },
         {
           "name": "actionLabel",
           "type": "string",
diff --git a/packages/ui/components/MegaMenu.wrn b/packages/ui/components/MegaMenu.wrn
index cad3a993..b969b2d1 100644
--- a/packages/ui/components/MegaMenu.wrn
+++ b/packages/ui/components/MegaMenu.wrn
@@ -34,6 +34,7 @@ component MegaMenu {
     panelAlign: string = "start"
     columnCount: number = 0
     fullWidth: boolean = false
+    openOnHover: boolean = true
     actionLabel: string = ""
     actionHref: string = ""
     actionIcon: string = "icon-[lucide--arrow-right]"
@@ -75,6 +76,20 @@ component MegaMenu {
       }
     }
 
+    client function activatePanel(sourceEvent) {
+      if (openOnHover) {
+        showPanel(sourceEvent)
+      } else {
+        togglePanel(sourceEvent)
+      }
+    }
+
+    client function hoverPanel(sourceEvent) {
+      if (openOnHover) {
+        showPanel(sourceEvent)
+      }
+    }
+
     client function handleKeydown(sourceEvent) {
       if (sourceEvent.key === "Escape" && visible) {
         sourceEvent.preventDefault()
@@ -113,9 +128,8 @@ component MegaMenu {
         class="wrn-mega__trigger"
         aria-haspopup="true"
         aria-expanded='{visible}'
-        @click='togglePanel(event)'
-        @mouseenter='showPanel(event)'
-        @focus='showPanel(event)'
+        @click='activatePanel(event)'
+        @mouseenter='hoverPanel(event)'
       >
         <span class='wrn-mega__trigger-icon {icon}' data-show="icon" aria-hidden="true"></span>
         <span class="wrn-mega__trigger-label">{label}</span>
@@ -274,7 +288,9 @@ component MegaMenu {
       left: 0;
       width: max-content;
       max-width: min(60rem, calc(100vw - 2rem));
+      max-height: calc(100dvh - 5.5rem);
       padding: 1rem;
+      overflow: hidden;
       border: 1px solid var(--wrn-color-border);
       border-radius: var(--wrn-radius-lg);
       background: var(--wrn-color-surface);
@@ -284,16 +300,19 @@ component MegaMenu {
     .wrn-mega[data-panel-width="lg"] .wrn-mega__panel { width: min(48rem, calc(100vw - 2rem)); }
     .wrn-mega[data-panel-width="xl"] .wrn-mega__panel { width: min(72rem, calc(100vw - 2rem)); }
     .wrn-mega[data-panel-width="2xl"] .wrn-mega__panel { width: min(88rem, calc(100vw - 2rem)); }
-    .wrn-mega[data-full-width="true"] .wrn-mega__panel { position: fixed; top: auto; right: 1rem; left: 1rem; width: auto; max-width: none; }
+    .wrn-mega[data-full-width="true"] .wrn-mega__panel { width: calc(100vw - 2rem); max-width: none; }
     .wrn-mega[data-panel-align="center"] .wrn-mega__panel { left: 50%; transform: translateX(-50%); }
     .wrn-mega[data-panel-align="end"] .wrn-mega__panel { right: 0; left: auto; }
 
-    .wrn-mega__layout { display: grid; grid-template-columns: auto minmax(0, 1fr) auto; gap: 1.25rem; }
+    .wrn-mega__layout { display: grid; min-height: 0; grid-template-columns: auto minmax(0, 1fr) auto; gap: 1.25rem; overflow: hidden; }
 
     .wrn-mega__columns {
       display: grid;
+      min-height: 0;
       grid-template-columns: repeat(auto-fit, minmax(13rem, 1fr));
       gap: 1.25rem;
+      overflow-y: auto;
+      overscroll-behavior: contain;
     }
 
     .wrn-mega[data-column-count="2"] .wrn-mega__columns { grid-template-columns: repeat(2, minmax(0, 1fr)); }
@@ -301,7 +320,7 @@ component MegaMenu {
     .wrn-mega[data-column-count="4"] .wrn-mega__columns { grid-template-columns: repeat(4, minmax(0, 1fr)); }
     .wrn-mega[data-column-count="5"] .wrn-mega__columns { grid-template-columns: repeat(5, minmax(0, 1fr)); }
 
-    .wrn-mega__rail { display: grid; min-width: 13rem; padding: 0.75rem; align-content: start; gap: 0.25rem; border-radius: var(--wrn-radius-lg); background: var(--wrn-color-surface-soft); }
+    .wrn-mega__rail { display: grid; min-width: 13rem; min-height: 0; padding: 0.75rem; align-content: start; gap: 0.25rem; overflow-y: auto; overscroll-behavior: contain; border-radius: var(--wrn-radius-lg); background: var(--wrn-color-surface-soft); }
     .wrn-mega__rail-link { display: flex; padding: 0.65rem; align-items: flex-start; gap: 0.65rem; color: var(--wrn-color-text); border-radius: var(--wrn-radius-sm); text-decoration: none; }
     .wrn-mega__rail-link:hover { background: var(--wrn-color-surface); }
     .wrn-mega__rail-link > span:last-child { display: grid; gap: 0.2rem; }
@@ -421,13 +440,16 @@ component MegaMenu {
         position: static;
         width: auto;
         max-width: 100%;
+        max-height: none;
+        overflow: visible;
         box-shadow: none;
       }
 
       .wrn-mega__columns {
         grid-template-columns: 1fr;
       }
-      .wrn-mega__layout { grid-template-columns: 1fr; }
+      .wrn-mega__layout { grid-template-columns: 1fr; overflow: visible; }
+      .wrn-mega__rail, .wrn-mega__columns { overflow: visible; }
       .wrn-mega__featured { width: auto; padding: 1rem 0 0; border-top: 1px solid var(--wrn-color-border); border-left: 0; }
       .wrn-mega[data-variant="icon-grid"] .wrn-mega__list { grid-template-columns: 1fr; }
     }
diff --git a/packages/ui/components/Navbar.wrn b/packages/ui/components/Navbar.wrn
index e6009fda..39bf4c49 100644
--- a/packages/ui/components/Navbar.wrn
+++ b/packages/ui/components/Navbar.wrn
@@ -196,6 +196,7 @@ size: string = "default"
                   panelAlign="{megaData(item).panelAlign || 'start'}"
                   columnCount="{megaData(item).columnCount || 0}"
                   fullWidth="{megaData(item).fullWidth || false}"
+                  openOnHover="{openOnHover}"
                   actionLabel="{megaData(item).actionLabel || ''}"
                   actionHref="{megaData(item).actionHref || ''}"
                   actionIcon="{megaData(item).actionIcon || 'icon-[lucide--arrow-right]'}"
diff --git a/packages/ui/package.json b/packages/ui/package.json
index 7cb0c7c3..cd9143d3 100644
--- a/packages/ui/package.json
+++ b/packages/ui/package.json
@@ -1,6 +1,6 @@
 {
   "name": "@wrnexus/ui",
-  "version": "0.8.29",
+  "version": "0.8.30",
   "private": true,
   "type": "module",
   "main": "src/index.ts",
diff --git a/packages/ui/test/ui.test.ts b/packages/ui/test/ui.test.ts
index fb3f9bb9..476cb9bd 100644
--- a/packages/ui/test/ui.test.ts
+++ b/packages/ui/test/ui.test.ts
@@ -3124,6 +3124,15 @@ test("mega menu bridges the gap between its trigger and panel", async () => {
   expect(source).toMatch(/\.wrn-mega__panel::before \{[^}]*bottom: 100%/s);
 });
 
+test("mega menu keeps hover activation and click activation from cancelling each other", () => {
+  const source = readFileSync(uiComponentPath("MegaMenu"), "utf8");
+  expect(source).toContain("openOnHover: boolean = true");
+  expect(source).toContain("@click='activatePanel(event)'");
+  expect(source).toContain("@mouseenter='hoverPanel(event)'");
+  expect(source).not.toContain("@focus='showPanel(event)'");
+  expect(source).toContain("max-height: calc(100dvh - 5.5rem)");
+});
+
 test("stepper shows only the active step content and offers back, next and skip", async () => {
   const source = readFileSync(uiComponentPath("Stepper"), "utf8");
   const html = await renderComponent(source, {