diff --git a/src/common/protojs.js b/src/common/protojs.js
index 026559b..a2e2d06 100644
--- a/src/common/protojs.js
+++ b/src/common/protojs.js
@@ -11,3 +11,26 @@
   }
   return object;
 }
+
+// The inverse function.
+export function inverseCorrectArrayKeys(input) {
+  if (Array.isArray(input)) {
+    if (input[0] === null || input[0] === undefined) {
+      // Make a copy of the input array so we don't modify the original one.
+      input = Array.from(input);
+      input.shift();
+    }
+    for (let i = 0; i < input.length; ++i) {
+      input[i] = inverseCorrectArrayKeys(input[i]);
+    }
+    return input;
+  }
+
+  if (typeof input !== 'object' || input === null) return input;
+
+  let array = [];
+  Object.entries(input).forEach(entry => {
+    array[entry[0] - 1] = inverseCorrectArrayKeys(entry[1]);
+  });
+  return array;
+}