Fix: logout instantly if backend connection not established or user not found in db

static/js/session-check.js

@@ -0,0 +1,46 @@
+(function () {
+	var path = window.location.pathname;
+	if (path === '/login/' || path === '/signup/') return;
+
+	// ── Save current page before navigating to login/signup ──
+	document.querySelectorAll('a[href="/login/"], a[href="/signup/"]').forEach(function (a) {
+		a.addEventListener('click', function () {
+			sessionStorage.setItem('f4_login_next', path);
+		});
+	});
+
+	// ── Validate session on every page load ──
+	if (!localStorage.getItem('f4_username')) return;
+
+	// Skip check if we just logged in (5 second grace period)
+	var loginTime = parseInt(localStorage.getItem('f4_login_time') || '0', 10);
+	if (Date.now() - loginTime < 5000) return;
+
+	fetch('https://backend.freedoms4.org/auth.php', {
+		method: 'POST',
+		headers: { 'Content-Type': 'application/json' },
+		credentials: 'include',
+		body: JSON.stringify({ action: 'check_session' }),
+	})
+		.then(function (r) {
+			return r.json();
+		})
+		.then(function (data) {
+			if (!data.valid) {
+				// DB gone, user deleted, or session invalid — log out immediately
+				localStorage.removeItem('f4_username');
+				localStorage.removeItem('f4_login_time');
+				localStorage.removeItem('f4_session_fails');
+				window.location.reload();
+			} else {
+				localStorage.removeItem('f4_session_fails');
+			}
+		})
+		.catch(function () {
+			// Backend completely unreachable — force logout immediately
+			localStorage.removeItem('f4_username');
+			localStorage.removeItem('f4_login_time');
+			localStorage.removeItem('f4_session_fails');
+			window.location.reload();
+		});
+})();