getVars: do not add same objects while concat

Author: nleush

lib/core.js

@@ -981,6 +981,8 @@
                                         allResults.vars[key] = v.concat(oldValue);
                                     }
 
+                                    allResults.vars[key] = filterSameObjects(allResults.vars[key]);
+
                                 } else {
                                     // Merge object mode.
                                     if (newValueOverrides) {

lib/utils.js

@@ -1496,3 +1496,14 @@ export function isBlocked(url, options, cb) {
             }
         });
 }
+
+export function filterSameObjects(array) {
+    const seen = new Set();
+    return array.filter(obj => {
+        // Generate JSON with sorted keys.
+        const key = JSON.stringify(Object.fromEntries(Object.entries(obj).sort(([a], [b]) => a.localeCompare(b))));
+        if (seen.has(key)) return false;
+        seen.add(key);
+        return true;
+    });
+}