show/hide password button

static/password-toggle.js

@@ -0,0 +1,16 @@
+// Toggle password visibility so users can check for typos, especially on mobile.
+document.querySelectorAll(".password-toggle").forEach(function (button) {
+  button.addEventListener("pointerdown", function (event) {
+    // Toggle on press (not click) for an instant response. preventScroll avoids
+    // a scroll-to-input animation that makes rapid toggling feel laggy, and
+    // keeping focus on the input keeps the mobile keyboard open.
+    event.preventDefault();
+    var input = document.getElementById(button.getAttribute("data-toggle-for"));
+    if (!input) return;
+    var showing = input.type === "text";
+    input.type = showing ? "password" : "text";
+    button.textContent = showing ? "Show" : "Hide";
+    button.setAttribute("aria-label", showing ? "Show password" : "Hide password");
+    input.focus({ preventScroll: true });
+  });
+});