diff --git a/src/webpack/webpack.ts b/src/webpack/webpack.ts
index f31855870..af57a324e 100644
--- a/src/webpack/webpack.ts
+++ b/src/webpack/webpack.ts
@@ -48,7 +48,7 @@ export const filters = {
         if (typeof m !== "function") return false;
         const s = Function.prototype.toString.call(m);
         for (const c of code) {
-            if (!s.includes(c)) return false;
+            if (s.indexOf(c) === -1) return false;
         }
         return true;
     },
@@ -229,7 +229,7 @@ export const findModuleId = traceFunction("findModuleId", function findModuleId(
         const str = String(wreq.m[id]);
 
         for (const c of code) {
-            if (!str.includes(c)) continue outer;
+            if (str.indexOf(c) === -1) continue outer;
         }
         return id;
     }
@@ -526,7 +526,7 @@ export function search(...filters: Array<string | RegExp>) {
         const factory = factories[id];
         const factoryStr = String(factory);
         for (const filter of filters) {
-            if (typeof filter === "string" && !factoryStr.includes(filter)) continue outer;
+            if (typeof filter === "string" && factoryStr.indexOf(filter) === -1) continue outer;
             if (filter instanceof RegExp && !filter.test(factoryStr)) continue outer;
         }
         results[id] = factory;