--- a/toolkit/components/extensions/test/mochitest/test_ext_webrequest.html
+++ b/toolkit/components/extensions/test/mochitest/test_ext_webrequest.html
@@ -438,19 +438,16 @@ function backgroundScript() {
     checkHeaders("response", details);
   }
 
   browser.webRequest.onBeforeRequest.addListener(onBeforeRequest, {urls: ["<all_urls>"]}, ["blocking"]);
   try {
     browser.webRequest.onBeforeRequest.addListener(onUpload, {urls: ["http://*/*"]}, ["blocking", "requestBody"]);
   } catch (e) {
     // requestBody is disabled in release builds
-    if (!/\brequestBody\b/.test(e.message)) {
-      throw e;
-    }
   }
   browser.webRequest.onBeforeSendHeaders.addListener(onBeforeSendHeaders, {urls: ["<all_urls>"]}, ["blocking", "requestHeaders"]);
   browser.webRequest.onSendHeaders.addListener(onSendHeaders, {urls: ["<all_urls>"]}, ["requestHeaders"]);
   browser.webRequest.onBeforeRedirect.addListener(onBeforeRedirect, {urls: ["<all_urls>"]});
   browser.webRequest.onHeadersReceived.addListener(onHeadersReceived, {urls: ["<all_urls>"]}, ["blocking", "responseHeaders"]);
   browser.webRequest.onResponseStarted.addListener(checkIpAndRecord.bind(null, "responseStarted"), {urls: ["<all_urls>"]});
   browser.webRequest.onResponseStarted.addListener(checkIpAndRecord.bind(null, "responseStarted2"), {urls: ["<all_urls>"]});
   browser.webRequest.onErrorOccurred.addListener(onErrorOccurred, {urls: ["<all_urls>"]});