diff --git a/extension/content/content.js b/extension/content/content.js
index c1882af..34c795b 100644
--- a/extension/content/content.js
+++ b/extension/content/content.js
@@ -18,6 +18,10 @@
   const PK_DROPDOWN_ID = "__pk_dropdown__";
   const VAULT_URL = "https://pwkeeper.ngodanguyen.tech/vault";
 
+  // Never inject on the PassKeeper vault itself — our own inputs would get decorated.
+  const OWN_ORIGINS = ["pwkeeper.ngodanguyen.tech"];
+  if (OWN_ORIGINS.includes(location.hostname)) return;
+
   let _bannerEl = null;
   let _hasNotifiedForm = false;
   let _formObserver = null;
@@ -107,7 +111,41 @@
       el.getAttribute("aria-label") || "",
     ].join(" ");
 
-    return CRED_HINTS.test(attrs);
+    if (!CRED_HINTS.test(attrs)) return false;
+
+    // Final gate: require a password field to be nearby (same form, or within
+    // 5 ancestor levels) — this prevents hooking standalone search / filter
+    // inputs that happen to carry a name like "user" or "email".
+    return _hasPasswordSibling(el);
+  }
+
+  /**
+   * Returns true when `el` shares a form (or close ancestor) with at least one
+   * visible password input. This is the key signal that we are on a login form,
+   * not a generic site-search or profile page.
+   */
+  function _hasPasswordSibling(el) {
+    // 1. Prefer the explicit <form> ancestor.
+    const form =
+      el.closest("form") || el.closest('[role="form"]');
+    if (form) {
+      return !!form.querySelector(
+        'input[type="password"]:not([disabled])',
+      );
+    }
+    // 2. No <form>? Walk up to 5 ancestor elements looking for a password input
+    //    in any subtree (covers React/Vue apps that render outside <form>).
+    let node = el.parentElement;
+    for (let i = 0; i < 5 && node; i++, node = node.parentElement) {
+      if (node.querySelector('input[type="password"]:not([disabled])')) {
+        return true;
+      }
+    }
+    // 3. Last resort: any visible password field on the entire page.
+    //    Only accept this if there is exactly one password field — avoids
+    //    false-positives on complex pages (account settings, checkout, etc.).
+    const pwFields = visiblePasswordFields();
+    return pwFields.length === 1;
   }
 
   function findUsernameField(pwField) {
@@ -827,6 +865,11 @@
    *   Pass nothing/undefined to let this function read storage itself.
    */
   async function decorateFields(knownItems) {
+    // Fast-path: if there are no password fields anywhere on the page, there is
+    // nothing to decorate. This prevents false-positive hooks on pages with
+    // standalone text inputs (search bars, filter fields, etc.).
+    if (!visiblePasswordFields().length) return;
+
     if (knownItems != null) {
       // Caller supplied pre-filtered items — trust them, skip the storage read.
       _matchingItems = knownItems;
@@ -1193,30 +1236,44 @@
       }
     });
 
+    // Debounce + narrow the MutationObserver: only re-scan when something that
+    // looks like a form input or a whole subtree with inputs was added/removed.
+    // This prevents constant re-scanning on SPA re-renders (tooltip shows,
+    // React state updates, etc.) that don't touch login form elements.
+    var _mutationTimer = null;
     _formObserver = new MutationObserver(function (mutations) {
-      // Ignore mutations caused by the extension's own injected elements
-      // (dropdown, icon buttons, save banner) to prevent re-decoration loops
-      // on SPAs that react to every DOM change.
-      var ownMutation = mutations.every(function (m) {
-        return Array.from(m.addedNodes)
-          .concat(Array.from(m.removedNodes))
-          .every(function (node) {
-            if (!node || node.nodeType !== 1) return true;
-            var cls = node.className || "";
-            var id = node.id || "";
-            return (
-              cls.indexOf("__pk") !== -1 ||
-              id.indexOf("__pk") !== -1 ||
-              (node.querySelector &&
-                (node.querySelector("." + PK_BTN_CLASS) ||
-                  node.querySelector("#" + PK_DROPDOWN_ID)))
-            );
-          });
+      // Ignore mutations caused by the extension's own injected elements.
+      var hasRelevantChange = mutations.some(function (m) {
+        // addedNodes contains an <input>, <form>, or a subtree with either.
+        return Array.from(m.addedNodes).some(function (node) {
+          if (!node || node.nodeType !== 1) return false;
+          // Skip our own injected nodes.
+          var cls = node.className || "";
+          var id = node.id || "";
+          if (cls.indexOf("__pk") !== -1 || id.indexOf("__pk") !== -1)
+            return false;
+          // A new <input> or <form> element, or a container with one inside.
+          var tag = node.tagName;
+          if (tag === "INPUT" || tag === "FORM") return true;
+          if (
+            node.querySelector &&
+            (node.querySelector('input[type="password"]') ||
+              node.querySelector("input") ||
+              node.querySelector("form"))
+          )
+            return true;
+          return false;
+        });
       });
-      if (ownMutation) return;
-      _hasNotifiedForm = false;
-      notifyFormDetected();
-      decorateFields();
+      if (!hasRelevantChange) return;
+
+      // Debounce: wait 300 ms after the last relevant mutation before scanning.
+      clearTimeout(_mutationTimer);
+      _mutationTimer = setTimeout(function () {
+        _hasNotifiedForm = false;
+        notifyFormDetected();
+        decorateFields();
+      }, 300);
     });
     _formObserver.observe(document.body, { childList: true, subtree: true });
   }