diff --git a/src/backend/extension/plasmo.ts b/src/backend/extension/plasmo.ts
index c13898be..14a5481f 100644
--- a/src/backend/extension/plasmo.ts
+++ b/src/backend/extension/plasmo.ts
@@ -19,9 +19,12 @@ export interface ExtensionMakeRequest extends ExtensionBaseRequest {
   url: string;
   method: string;
   headers?: Record<string, string>;
-  body?: string | FormData | URLSearchParams | Record<string, any>;
+  body?: string | Record<string, any>;
+  bodyType?: "string" | "FormData" | "URLSearchParams" | "object";
 }
 
+export type ExtensionMakeRequestBodyType = ExtensionMakeRequest["bodyType"];
+
 export type ExtensionMakeRequestResponse<T> = ExtensionBaseResponse<{
   response: {
     statusCode: number;
diff --git a/src/backend/extension/request.ts b/src/backend/extension/request.ts
new file mode 100644
index 00000000..5885225e
--- /dev/null
+++ b/src/backend/extension/request.ts
@@ -0,0 +1,17 @@
+import { ExtensionMakeRequestBodyType } from "./plasmo";
+
+export function getBodyTypeFromBody(
+  body: unknown,
+): ExtensionMakeRequestBodyType {
+  if (typeof body === "string") return "string";
+  if (body instanceof FormData) return "FormData";
+  if (body instanceof URLSearchParams) return "URLSearchParams";
+  return "object";
+}
+
+export function convertBodyToObject(body: unknown): any {
+  if (body instanceof FormData || body instanceof URLSearchParams) {
+    return [...body];
+  }
+  return body;
+}
diff --git a/src/backend/providers/fetchers.ts b/src/backend/providers/fetchers.ts
index 95267595..5cb6f6ba 100644
--- a/src/backend/providers/fetchers.ts
+++ b/src/backend/providers/fetchers.ts
@@ -4,6 +4,8 @@ import { sendExtensionRequest } from "@/backend/extension/messaging";
 import { getApiToken, setApiToken } from "@/backend/helpers/providerApi";
 import { getProviderApiUrls, getProxyUrls } from "@/utils/proxyUrls";
 
+import { convertBodyToObject, getBodyTypeFromBody } from "../extension/request";
+
 function makeLoadbalancedList(getter: () => string[]) {
   let listIndex = -1;
   return () => {
@@ -67,10 +69,12 @@ function makeFinalHeaders(
 
 export function makeExtensionFetcher() {
   const fetcher: Fetcher = async (url, ops) => {
-    const result = (await sendExtensionRequest<any>({
+    const result = await sendExtensionRequest<any>({
       url,
       ...ops,
-    })) as any;
+      body: convertBodyToObject(ops.body),
+      bodyType: getBodyTypeFromBody(ops.body),
+    });
     if (!result?.success) throw new Error(`extension error: ${result?.error}`);
     const res = result.response;
     return {