diff --git a/dom/base/nsXMLHttpRequest.cpp b/dom/base/nsXMLHttpRequest.cpp
index dbd0d69c7d1..c7d2869c756 100644
--- a/dom/base/nsXMLHttpRequest.cpp
+++ b/dom/base/nsXMLHttpRequest.cpp
@@ -3104,13 +3104,8 @@ nsXMLHttpRequest::SetRequestHeader(const nsACString& header,
     mergeHeaders = false;
   }
 
-  nsresult rv;
-  if (value.IsEmpty()) {
-    rv = httpChannel->SetEmptyRequestHeader(header);
-  } else {
-    // Merge headers depending on what we decided above.
-    rv = httpChannel->SetRequestHeader(header, value, mergeHeaders);
-  }
+  // Merge headers depending on what we decided above.
+  nsresult rv = httpChannel->SetRequestHeader(header, value, mergeHeaders);
   if (rv == NS_ERROR_INVALID_ARG) {
     return NS_ERROR_DOM_SYNTAX_ERR;
   }
@@ -3451,13 +3446,9 @@ nsXMLHttpRequest::OnRedirectVerifyCallback(nsresult result)
       // Ensure all original headers are duplicated for the new channel (bug #553888)
       for (uint32_t i = mModifiedRequestHeaders.Length(); i > 0; ) {
         --i;
-        if (mModifiedRequestHeaders[i].value.IsEmpty()) {
-          httpChannel->SetEmptyRequestHeader(mModifiedRequestHeaders[i].header);
-        } else {
-          httpChannel->SetRequestHeader(mModifiedRequestHeaders[i].header,
-                                        mModifiedRequestHeaders[i].value,
-                                        false);
-        }
+        httpChannel->SetRequestHeader(mModifiedRequestHeaders[i].header,
+                                      mModifiedRequestHeaders[i].value,
+                                      false);
       }
     }
   } else {
diff --git a/dom/workers/test/serviceworkers/fetch/fetch_tests.js b/dom/workers/test/serviceworkers/fetch/fetch_tests.js
index 0a12c2941fb..c46bcff9b72 100644
--- a/dom/workers/test/serviceworkers/fetch/fetch_tests.js
+++ b/dom/workers/test/serviceworkers/fetch/fetch_tests.js
@@ -185,12 +185,6 @@ fetchXHR('redirect_serviceworker.sjs', function(xhr) {
   finish();
 });
 
-fetchXHR('empty-header', function(xhr) {
-  my_ok(xhr.status == 200, "load should be successful");
-  my_ok(xhr.responseText == "emptyheader", "load should have the expected content");
-  finish();
-}, null, [["emptyheader", ""]]);
-
 expectAsyncResult();
 fetch('http://example.com/tests/dom/security/test/cors/file_CrossSiteXHR_server.sjs?status=200&allowOrigin=*')
 .then(function(res) {
diff --git a/dom/workers/test/test_xhr_headers.html b/dom/workers/test/test_xhr_headers.html
index 9786a15e4b5..bfafe12cf4a 100644
--- a/dom/workers/test/test_xhr_headers.html
+++ b/dom/workers/test/test_xhr_headers.html
@@ -31,7 +31,6 @@ info("Informing server about the current host");
 var xhr = new XMLHttpRequest();
 xhr.open("POST", path + serverFilename);
 xhr.setRequestHeader("options-host", otherHost);
-xhr.setRequestHeader("empty", "");
 xhr.onreadystatechange = function() {
   if (xhr.readyState == 4) {
     info("Launching worker");
diff --git a/dom/workers/test/xhr_headers_server.sjs b/dom/workers/test/xhr_headers_server.sjs
index 9a12fddfbb1..045c999b997 100644
--- a/dom/workers/test/xhr_headers_server.sjs
+++ b/dom/workers/test/xhr_headers_server.sjs
@@ -14,16 +14,9 @@ function handleRequest(request, response) {
       if (optionsHost) {
         setState("postHost", request.host);
         setState("optionsHost", optionsHost);
+        return;
       }
-
-      try {
-        var emptyHeader = "nada" + request.getHeader("empty");
-      } catch(e) { }
-
-      if (emptyHeader && emptyHeader == "nada") {
-        setState("emptyHeader", "nada");
-      }
-      return;
+      break;
 
     case "OPTIONS":
       if (getState("optionsHost") == request.host) {
@@ -39,8 +32,7 @@ function handleRequest(request, response) {
       response.setHeader("Cache-Control", "no-cache", false);
       response.setHeader("Content-Type", "text/plain", false);
 
-      if (getState("postHost") == request.host &&
-          getState("emptyHeader") == "nada") {
+      if (getState("postHost") == request.host) {
         var result = getState("optionsHeader");
         if (result) {
           response.write("Success: expected OPTIONS request with " + result +
diff --git a/testing/web-platform/meta/XMLHttpRequest/setrequestheader-allow-empty-value.htm.ini b/testing/web-platform/meta/XMLHttpRequest/setrequestheader-allow-empty-value.htm.ini
new file mode 100644
index 00000000000..6ca1f1ba844
--- /dev/null
+++ b/testing/web-platform/meta/XMLHttpRequest/setrequestheader-allow-empty-value.htm.ini
@@ -0,0 +1,5 @@
+[setrequestheader-allow-empty-value.htm]
+  type: testharness
+  [XMLHttpRequest: setRequestHeader() - empty header ()]
+    expected: FAIL
+