diff --git a/.eslintrc.json b/.eslintrc.json
index 3d56f5861f..5f9db07aa3 100644
--- a/.eslintrc.json
+++ b/.eslintrc.json
@@ -347,7 +347,11 @@
             }
         },
         {
-            "files": ["frontend_tests/casper_lib/**", "frontend_tests/casper_tests/**"],
+            "files": [
+                "frontend_tests/casper_lib/**",
+                "frontend_tests/casper_tests/**",
+                "tools/debug-require.js"
+            ],
             "env": {
                 "browser": true,
                 "es2020": false
diff --git a/tools/debug-require.js b/tools/debug-require.js
index 596c6feb6f..2aa998e143 100644
--- a/tools/debug-require.js
+++ b/tools/debug-require.js
@@ -1,12 +1,12 @@
 /* global __webpack_require__ */
 
-let webpackModules;
+var webpackModules;
 
 function debugRequire(request) {
     if (!Object.prototype.hasOwnProperty.call(debugRequire.ids, request)) {
         throw new Error("Cannot find module '" + request + "'");
     }
-    const moduleId = debugRequire.ids[request];
+    var moduleId = debugRequire.ids[request];
     if (!Object.prototype.hasOwnProperty.call(webpackModules, moduleId)) {
         throw new Error("Module '" + request + "' has not been loaded yet");
     }