diff --git a/lib/core.js b/lib/core.js
index 888b8e986..365a54c20 100644
--- a/lib/core.js
+++ b/lib/core.js
@@ -1602,7 +1602,7 @@
         /*
         Convert '?_option=value' to 
         {
-            options: value
+            option: value
         }
         */
         var result = {};
@@ -1745,7 +1745,7 @@
                 providerOptionsValue = options.getProviderOptions(path, defaultValue);
             }
 
-            // `_.` has top priority.
+            // `_key` has top priority.
             var value = options.getProviderOptions(alternatePath, providerOptionsValue);
 
             if (
@@ -1771,7 +1771,7 @@
 
             const bits = path.split('.');
 
-            const alternatePath = path.replace(/^[^.]+\./, '_');    // "robot.prerender" -> "_.prerender"
+            const alternatePath = path.replace(/^[^.]+\./, '_');    // "robot.prerender" -> "_prerender"
             
             // p1.
             var value = options.getProviderOptions(alternatePath);
diff --git a/lib/fetch.js b/lib/fetch.js
index c19d85349..34f09c979 100644
--- a/lib/fetch.js
+++ b/lib/fetch.js
@@ -416,26 +416,30 @@ class HostAbortController {
 }
 
 const cookiesOptions = [
-    'Domain',
-    'Expires',
-    'HttpOnly',
-    'Max-Age',
-    'Partitioned',
-    'Path',
-    'Secure',
-    'SameSite',
+    'domain',
+    'expires',
+    'httponly',
+    'max-age',
+    'partitioned',
+    'path',
+    'secure',
+    'samesite',
 ];
 
+// Keep cookie values verbatim: default decode/encode (decodeURIComponent/encodeURIComponent)
+// corrupts base64 values containing '/', '+', '=' on round-trip.
+const identity = v => v;
+
 export function extendCookiesJar(uri, jar, headers) {
     var cookiesValue = headers && headers['set-cookie'];
     if (cookiesValue) {
         var cookiesArray = Array.isArray(cookiesValue) ? cookiesValue : [cookiesValue];
         try {
             var cookies = cookiesArray.reduce((allCookies, cookieStr) => {
-                return { ...allCookies, ...parseCookie(cookieStr) };
+                return { ...allCookies, ...parseCookie(cookieStr, { decode: identity }) };
             }, {});
             // Filter cookies options.
-            cookies = Object.fromEntries(Object.entries(cookies).filter(([k,v]) => !cookiesOptions.includes(k)));
+            cookies = Object.fromEntries(Object.entries(cookies).filter(([k,v]) => !cookiesOptions.includes(k.toLowerCase())));
             jar = jar || {};
             jar = {...jar, ...cookies};
         } catch(ex) {
@@ -448,7 +452,7 @@ export function extendCookiesJar(uri, jar, headers) {
 export function setCookieFromJar(uri, headers, jar) {
     if (jar) {
         try{
-            var cookies = Object.entries(jar).map(([k,v]) => serializeCookie(k, v)).join('; ');
+            var cookies = Object.entries(jar).map(([k,v]) => serializeCookie(k, v, { encode: identity })).join('; ');
             headers['Cookie'] = cookies;
         } catch(ex) {
             log('Error serialize cookie', uri, ex.message);
diff --git a/views/debug.ejs b/views/debug.ejs
index c635a1bb7..d999add2c 100644
--- a/views/debug.ejs
+++ b/views/debug.ejs
@@ -14,7 +14,7 @@
         var baseAppUrl = <%- JSON.stringify(CONFIG.baseAppUrl) %>;
         var REL_GROUPS = <%- JSON.stringify(CONFIG.REL_GROUPS) %>;
         var DEBUG = <%= JSON.stringify(DEBUG) %>;
-        var QUERY = <%- JSON.stringify(QUERY) %>;
+        var QUERY = <%- JSON.stringify(QUERY).replace(/</g, '\\u003c') %>;
     </script>
 </head>
 <body>