diff --git a/ChangeLog b/ChangeLog
index 5f3ae63570..b687d9d18b 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -28,6 +28,7 @@ phpMyAdmin - ChangeLog
 - issue #11628 Proper parsing of INSERT ... ON DUPLICATE KEY queries
 - issue #12545 Proper parsing of CREATE TABLE ... PARTITION queries
 - issue #12473 Code can throw unhandled exception
+- issue #12550 Do not try to keep alive session even after expiry
 
 4.6.4 (2016-08-16)
 - issue        [security] Weaknesses with cookie encryption, see PMASA-2016-29
diff --git a/js/functions.js b/js/functions.js
index 99eff84673..9fa445f314 100644
--- a/js/functions.js
+++ b/js/functions.js
@@ -903,13 +903,13 @@ AJAX.registerOnload('functions.js', function () {
                 data: params,
                 success: function (data) {
                     if (data.success) {
-                        if (PMA_commonParams.get('LoginCookieValidity')-_idleSecondsCounter > 5) {
-                            var interval = (PMA_commonParams.get('LoginCookieValidity') - _idleSecondsCounter - 5) * 1000;
-                            if (interval > Math.pow(2, 31) - 1) { // max value for setInterval() function
-                                interval = Math.pow(2, 31) - 1;
-                            }
+                        var remaining = PMA_commonParams.get('LoginCookieValidity') - _idleSecondsCounter;
+                        if (remaining > 5) {
+                            // max value for setInterval() function
+                            var interval = min(remaining * 1000, Math.pow(2, 31) - 1);
                             updateTimeout = window.setTimeout(UpdateIdleTime, interval);
-                        } else {
+                        } else if (remaining > 0) {
+                            // We're close to session expiry
                             updateTimeout = window.setTimeout(UpdateIdleTime, 2000);
                         }
                     } else { //timeout occurred