Index: admin_templates/incs/close_popup.tpl
===================================================================
--- admin_templates/incs/close_popup.tpl	(revision 14888)
+++ admin_templates/incs/close_popup.tpl	(working copy)
@@ -12,7 +12,7 @@
 			var $modal_windows = <inp2:m_if check="adm_UsePopups" mode="modal">true<inp2:m_else/>false</inp2:m_if>;
 
 			if ($is_debug) {
-				document.write('<a href="#" onclick="proceed_redirect()">' + $redirect_url.replace('%5C', '\\') + '</a>');
+				document.write('<a href="#" onclick="proceed_redirect()">' + $redirect_url.replace(/%5C/g, '\\') + '</a>');
 			}
 			else {
 				proceed_redirect();
@@ -43,7 +43,7 @@
 				}
 				else if (!$use_popups) {
 					// not using popups (for editing), but close_popup called (e.g. from selector)
-					window.location.href = $redirect_url.replace('%5C', '\\');
+					window.location.href = $redirect_url.replace(/%5C/g, '\\');
 				}
 			}
 
Index: admin_templates/js/script.js
===================================================================
--- admin_templates/js/script.js	(revision 14888)
+++ admin_templates/js/script.js	(working copy)
@@ -1817,7 +1817,7 @@
 		// setTimeout allows to call method indirectly. Without it whole idea won't work 2nd time (try adding 2 relations one after another)
 		setTimeout(
 			function() {
-				openSelector('adm', $ru.replace('%5C', '\\') + '&merge_opener_stack=1');
+				openSelector('adm', $ru.replace(/%5C/g, '\\') + '&merge_opener_stack=1');
 			},
 			200
 		);
@@ -1828,7 +1828,7 @@
 	window.focus();
 
 	if ( !(($force_skip_refresh === true) || (typeof $skip_refresh != 'undefined' && $skip_refresh)) ) {
-		window.location.href = $redirect_url.replace('%5C', '\\');
+		window.location.href = $redirect_url.replace(/%5C/g, '\\');
 	}
 }
 
Index: kernel/utility/opener_stack.php
===================================================================
--- kernel/utility/opener_stack.php	(revision 14888)
+++ kernel/utility/opener_stack.php	(working copy)
@@ -130,12 +130,14 @@
 			return $this->data[$index];
 		}
 
-		list ($index_file, $env) = explode('|', $this->data[$index], 2);
-		$params = $this->Application->processQueryString($env, 'pass');
+		list ($index_file, $original_env) = explode('|', $this->data[$index], 2);
 
+		$fixed_env = str_replace(Array ('&amp;', '%5C'), Array ('&', '\\'), $original_env);
+		$params = $this->Application->processQueryString($fixed_env, 'pass');
+
 		// detect "__URLENCODE__" parameter value, used when opener stack element was built
 		// without it rebuilding opener stack element will convert all "&" to "&amp;" elements
-		$params['__URLENCODE__'] = (strpos($env, '&') !== false && strpos($env, '&amp;') === false) || (strpos($env, '\\') !== false && strpos($env, '%5C') === false) ? 1 : 0;
+		$params['__URLENCODE__'] = $original_env != $fixed_env ? 1 : 0;
 
 		$template = kUtil::popParam('t', $params, '');