diff --git a/dom/base/nsFrameLoader.cpp b/dom/base/nsFrameLoader.cpp
index d51462b63402..b2f007096b54 100644
--- a/dom/base/nsFrameLoader.cpp
+++ b/dom/base/nsFrameLoader.cpp
@@ -47,6 +47,7 @@
 #include "nsBaseWidget.h"
 #include "nsQueryObject.h"
 #include "ReferrerInfo.h"
+#include "nsIOpenWindowInfo.h"
 
 #include "nsIURI.h"
 #include "nsNetUtil.h"
@@ -257,7 +258,12 @@ static bool IsTopContent(BrowsingContext* aParent, Element* aOwner) {
 }
 
 static already_AddRefed<BrowsingContext> CreateBrowsingContext(
-    Element* aOwner, BrowsingContext* aOpener) {
+    Element* aOwner, nsIOpenWindowInfo* aOpenWindowInfo) {
+  RefPtr<BrowsingContext> opener;
+  if (aOpenWindowInfo && !aOpenWindowInfo->GetForceNoOpener()) {
+    opener = aOpenWindowInfo->GetParent();
+  }
+
   Document* doc = aOwner->OwnerDoc();
   // Get our parent docshell off the document of mOwnerContent
   // XXXbz this is such a total hack.... We really need to have a
@@ -290,7 +296,7 @@ static already_AddRefed<BrowsingContext> CreateBrowsingContext(
   if (IsTopContent(parentContext, aOwner)) {
     // Create toplevel content without a parent & as Type::Content.
     RefPtr<BrowsingContext> bc = BrowsingContext::CreateDetached(
-        nullptr, aOpener, frameName, BrowsingContext::Type::Content);
+        nullptr, opener, frameName, BrowsingContext::Type::Content);
 
     // If this is a mozbrowser frame, pretend it's windowless so that it gets
     // ownership of its BrowsingContext even though it's a top-level content
@@ -304,10 +310,13 @@ static already_AddRefed<BrowsingContext> CreateBrowsingContext(
     return bc.forget();
   }
 
+  MOZ_ASSERT(!aOpenWindowInfo,
+             "Can't have openWindowInfo for non-toplevel context");
+
   auto type = parentContext->IsContent() ? BrowsingContext::Type::Content
                                          : BrowsingContext::Type::Chrome;
 
-  return BrowsingContext::CreateDetached(parentContext, aOpener, frameName,
+  return BrowsingContext::CreateDetached(parentContext, nullptr, frameName,
                                          type);
 }
 
@@ -339,9 +348,8 @@ static bool InitialLoadIsRemote(Element* aOwner) {
                              nsGkAtoms::_true, eCaseMatters);
 }
 
-already_AddRefed<nsFrameLoader> nsFrameLoader::Create(Element* aOwner,
-                                                      BrowsingContext* aOpener,
-                                                      bool aNetworkCreated) {
+already_AddRefed<nsFrameLoader> nsFrameLoader::Create(
+    Element* aOwner, bool aNetworkCreated, nsIOpenWindowInfo* aOpenWindowInfo) {
   NS_ENSURE_TRUE(aOwner, nullptr);
   Document* doc = aOwner->OwnerDoc();
 
@@ -370,7 +378,8 @@ already_AddRefed<nsFrameLoader> nsFrameLoader::Create(Element* aOwner,
                       doc->IsStaticDocument()),
                  nullptr);
 
-  RefPtr<BrowsingContext> context = CreateBrowsingContext(aOwner, aOpener);
+  RefPtr<BrowsingContext> context =
+      CreateBrowsingContext(aOwner, aOpenWindowInfo);
   NS_ENSURE_TRUE(context, nullptr);
 
   // Determine the initial RemoteType from the load environment. An empty or
@@ -378,8 +387,6 @@ already_AddRefed<nsFrameLoader> nsFrameLoader::Create(Element* aOwner,
   // denotes a remote frame.
   nsAutoString remoteType(VoidString());
   if (InitialLoadIsRemote(aOwner)) {
-    MOZ_ASSERT(!aOpener, "Cannot pass `aOpener` for a remote frame!");
-
     // If the `remoteType` attribute is specified and valid, use it. Otherwise,
     // use a default remote type.
     bool hasRemoteType =
@@ -391,6 +398,7 @@ already_AddRefed<nsFrameLoader> nsFrameLoader::Create(Element* aOwner,
 
   RefPtr<nsFrameLoader> fl =
       new nsFrameLoader(aOwner, context, remoteType, aNetworkCreated);
+  fl->mOpenWindowInfo = aOpenWindowInfo;
   return fl.forget();
 }
 
@@ -411,7 +419,7 @@ already_AddRefed<nsFrameLoader> nsFrameLoader::Recreate(
 
   RefPtr<BrowsingContext> context = aContext;
   if (!context) {
-    context = CreateBrowsingContext(aOwner, /* opener */ nullptr);
+    context = CreateBrowsingContext(aOwner, /* openWindowInfo */ nullptr);
   }
   NS_ENSURE_TRUE(context, nullptr);
 
@@ -2478,20 +2486,15 @@ bool nsFrameLoader::TryRemoteBrowserInternal() {
     return false;
   }
 
+  uint64_t nextRemoteBrowserId =
+      mOpenWindowInfo ? mOpenWindowInfo->GetNextRemoteBrowserId() : 0;
+
   if (!EnsureBrowsingContextAttached()) {
     return false;
   }
 
   RefPtr<ContentParent> openerContentParent;
-  RefPtr<nsIPrincipal> openerContentPrincipal;
   RefPtr<BrowserParent> sameTabGroupAs;
-  if (auto* host = BrowserHost::GetFrom(parentDocShell->GetOpener())) {
-    openerContentParent = host->GetContentParent();
-    BrowserParent* openerBrowserParent = host->GetActor();
-    if (openerBrowserParent) {
-      openerContentPrincipal = openerBrowserParent->GetContentPrincipal();
-    }
-  }
 
   // <iframe mozbrowser> gets to skip these checks.
   // iframes for JS plugins also get to skip these checks. We control the URL
@@ -2557,32 +2560,11 @@ bool nsFrameLoader::TryRemoteBrowserInternal() {
   nsresult rv = GetNewTabContext(&context);
   NS_ENSURE_SUCCESS(rv, false);
 
-  // We need to propagate the first party domain if the opener is presented.
-  if (openerContentPrincipal) {
-    context.SetFirstPartyDomainAttributes(
-        openerContentPrincipal->OriginAttributesRef().mFirstPartyDomain);
-  }
-
-  uint64_t nextRemoteTabId = 0;
-  if (mOwnerContent) {
-    nsAutoString nextBrowserParentIdAttr;
-    mOwnerContent->GetAttr(kNameSpaceID_None, nsGkAtoms::nextRemoteTabId,
-                           nextBrowserParentIdAttr);
-    nextRemoteTabId = strtoull(
-        NS_ConvertUTF16toUTF8(nextBrowserParentIdAttr).get(), nullptr, 10);
-
-    // We may be in a window that was just opened, so try the
-    // nsIBrowserDOMWindow API as a backup.
-    if (!nextRemoteTabId && window) {
-      Unused << window->GetNextRemoteTabId(&nextRemoteTabId);
-    }
-  }
-
   nsCOMPtr<Element> ownerElement = mOwnerContent;
 
   mRemoteBrowser = ContentParent::CreateBrowser(
       context, ownerElement, mRemoteType, mPendingBrowsingContext,
-      openerContentParent, nextRemoteTabId);
+      openerContentParent, nextRemoteBrowserId);
   if (!mRemoteBrowser) {
     return false;
   }
@@ -2592,7 +2574,7 @@ bool nsFrameLoader::TryRemoteBrowserInternal() {
   // detach our original BC and take ownership of the one from the remote
   // browser.
   if (mPendingBrowsingContext != mRemoteBrowser->GetBrowsingContext()) {
-    MOZ_DIAGNOSTIC_ASSERT(nextRemoteTabId);
+    MOZ_DIAGNOSTIC_ASSERT(nextRemoteBrowserId);
     mPendingBrowsingContext->Detach();
     mPendingBrowsingContext = mRemoteBrowser->GetBrowsingContext();
   }
@@ -3337,14 +3319,6 @@ void nsFrameLoader::MaybeUpdatePrimaryBrowserParent(
 
 nsresult nsFrameLoader::GetNewTabContext(MutableTabContext* aTabContext,
                                          nsIURI* aURI) {
-  OriginAttributes attrs;
-  nsresult rv;
-
-  // set the userContextId on the attrs before we pass them into
-  // the tab context
-  rv = PopulateOriginContextIdsFromAttributes(attrs);
-  NS_ENSURE_SUCCESS(rv, rv);
-
   nsAutoString presentationURLStr;
   mOwnerContent->GetAttr(kNameSpaceID_None, nsGkAtoms::mozpresentation,
                          presentationURLStr);
@@ -3353,8 +3327,8 @@ nsresult nsFrameLoader::GetNewTabContext(MutableTabContext* aTabContext,
   nsCOMPtr<nsILoadContext> parentContext = do_QueryInterface(docShell);
   NS_ENSURE_STATE(parentContext);
 
-  bool isPrivate = parentContext->UsePrivateBrowsing();
-  attrs.SyncAttributesWithPrivateBrowsing(isPrivate);
+  MOZ_ASSERT(mPendingBrowsingContext->EverAttached());
+  OriginAttributes attrs = mPendingBrowsingContext->OriginAttributesRef();
 
   UIStateChangeType showFocusRings = UIStateChangeType_NoChange;
   uint64_t chromeOuterWindowID = 0;
diff --git a/dom/base/nsFrameLoader.h b/dom/base/nsFrameLoader.h
index fae0166d010c..8c43bdb39375 100644
--- a/dom/base/nsFrameLoader.h
+++ b/dom/base/nsFrameLoader.h
@@ -45,6 +45,7 @@ class nsIMessageSender;
 class nsIPrintSettings;
 class nsIWebBrowserPersistDocumentReceiver;
 class nsIWebProgressListener;
+class nsIOpenWindowInfo;
 
 namespace mozilla {
 
@@ -101,9 +102,9 @@ class nsFrameLoader final : public nsStubMutationObserver,
 
  public:
   // Called by Frame Elements to create a new FrameLoader.
-  static already_AddRefed<nsFrameLoader> Create(Element* aOwner,
-                                                BrowsingContext* aOpener,
-                                                bool aNetworkCreated);
+  static already_AddRefed<nsFrameLoader> Create(
+      Element* aOwner, bool aNetworkCreated,
+      nsIOpenWindowInfo* aOpenWindowInfo = nullptr);
 
   // Called by nsFrameLoaderOwner::ChangeRemoteness when switching out
   // FrameLoaders.
@@ -476,6 +477,7 @@ class nsFrameLoader final : public nsStubMutationObserver,
   nsCOMPtr<nsIURI> mURIToLoad;
   nsCOMPtr<nsIPrincipal> mTriggeringPrincipal;
   nsCOMPtr<nsIContentSecurityPolicy> mCsp;
+  nsCOMPtr<nsIOpenWindowInfo> mOpenWindowInfo;
   mozilla::dom::Element* mOwnerContent;  // WEAK
 
   // After the frameloader has been removed from the DOM but before all of the
diff --git a/dom/base/nsObjectLoadingContent.cpp b/dom/base/nsObjectLoadingContent.cpp
index 55feb0c6322d..1de6f3acd2aa 100644
--- a/dom/base/nsObjectLoadingContent.cpp
+++ b/dom/base/nsObjectLoadingContent.cpp
@@ -521,8 +521,7 @@ void nsObjectLoadingContent::SetupFrameLoader(int32_t aJSPluginId) {
   NS_ASSERTION(thisContent, "must be a content");
 
   mFrameLoader =
-      nsFrameLoader::Create(thisContent->AsElement(),
-                            /* aOpener = */ nullptr, mNetworkCreated);
+      nsFrameLoader::Create(thisContent->AsElement(), mNetworkCreated);
   MOZ_ASSERT(mFrameLoader, "nsFrameLoader::Create failed");
 }
 
@@ -2546,7 +2545,7 @@ void nsObjectLoadingContent::CreateStaticClone(
     nsCOMPtr<nsIContent> content =
         do_QueryInterface(static_cast<nsIImageLoadingContent*>(aDest));
     RefPtr<nsFrameLoader> fl =
-        nsFrameLoader::Create(content->AsElement(), nullptr, false);
+        nsFrameLoader::Create(content->AsElement(), false);
     if (fl) {
       aDest->mFrameLoader = fl;
       mFrameLoader->CreateStaticClone(fl);
diff --git a/dom/html/nsGenericHTMLFrameElement.cpp b/dom/html/nsGenericHTMLFrameElement.cpp
index 0c008bd665d2..99eddc29691b 100644
--- a/dom/html/nsGenericHTMLFrameElement.cpp
+++ b/dom/html/nsGenericHTMLFrameElement.cpp
@@ -130,7 +130,7 @@ void nsGenericHTMLFrameElement::EnsureFrameLoader() {
 
   // Strangely enough, this method doesn't actually ensure that the
   // frameloader exists.  It's more of a best-effort kind of thing.
-  mFrameLoader = nsFrameLoader::Create(this, mOpenerWindow, mNetworkCreated);
+  mFrameLoader = nsFrameLoader::Create(this, mNetworkCreated);
 }
 
 void nsGenericHTMLFrameElement::DisallowCreateFrameLoader() {
@@ -370,7 +370,7 @@ nsresult nsGenericHTMLFrameElement::CopyInnerTo(Element* aDest) {
   if (doc->IsStaticDocument() && mFrameLoader) {
     nsGenericHTMLFrameElement* dest =
         static_cast<nsGenericHTMLFrameElement*>(aDest);
-    RefPtr<nsFrameLoader> fl = nsFrameLoader::Create(dest, nullptr, false);
+    RefPtr<nsFrameLoader> fl = nsFrameLoader::Create(dest, false);
     NS_ENSURE_STATE(fl);
     dest->mFrameLoader = fl;
     mFrameLoader->CreateStaticClone(fl);
diff --git a/dom/interfaces/base/nsIBrowser.idl b/dom/interfaces/base/nsIBrowser.idl
index d3c512df6cea..242c6b98cc4f 100644
--- a/dom/interfaces/base/nsIBrowser.idl
+++ b/dom/interfaces/base/nsIBrowser.idl
@@ -9,6 +9,7 @@ interface nsITransportSecurityInfo;
 interface nsIURI;
 interface nsIWebProgress;
 interface nsIReferrerInfo;
+interface nsIOpenWindowInfo;
 
 webidl FrameLoader;
 
@@ -24,6 +25,12 @@ interface nsIBrowser : nsISupports
    */
   readonly attribute FrameLoader sameProcessAsFrameLoader;
 
+  /**
+   * Gets the optional open window information provided by the window creation
+   * code and used to initialize a new browser.
+   */
+  attribute nsIOpenWindowInfo openWindowInfo;
+
   /*
    * Called by the child to inform the parent that links are dropped into
    * content area.
diff --git a/dom/xul/XULFrameElement.cpp b/dom/xul/XULFrameElement.cpp
index 88b844af6f9c..9f5a057ed8bd 100644
--- a/dom/xul/XULFrameElement.cpp
+++ b/dom/xul/XULFrameElement.cpp
@@ -5,7 +5,9 @@
  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
 
 #include "nsCOMPtr.h"
+#include "nsIBrowser.h"
 #include "nsIContent.h"
+#include "nsIOpenWindowInfo.h"
 #include "nsFrameLoader.h"
 #include "mozilla/AsyncEventDispatcher.h"
 #include "mozilla/dom/HTMLIFrameElement.h"
@@ -75,24 +77,20 @@ void XULFrameElement::LoadSrc() {
   }
   RefPtr<nsFrameLoader> frameLoader = GetFrameLoader();
   if (!frameLoader) {
-    // Check if we have an opener we need to be setting
-    RefPtr<BrowsingContext> opener = mOpener;
-    if (!opener) {
-      // If we are a primary xul-browser, we want to take the opener property!
-      nsCOMPtr<nsPIDOMWindowOuter> window = OwnerDoc()->GetWindow();
-      if (AttrValueIs(kNameSpaceID_None, nsGkAtoms::primary, nsGkAtoms::_true,
-                      eIgnoreCase) &&
-          window) {
-        opener = window->TakeOpenerForInitialContentBrowser();
-      }
+    // We may have had a nsIOpenWindowInfo set on our nsIBrowser by browser
+    // chrome, due to being used as the target for a `window.open` call. Fetch
+    // that information if it's available, and clear it out so we don't read it
+    // again.
+    nsCOMPtr<nsIOpenWindowInfo> openWindowInfo;
+    if (nsCOMPtr<nsIBrowser> browser = AsBrowser()) {
+      browser->GetOpenWindowInfo(getter_AddRefs(openWindowInfo));
+      browser->SetOpenWindowInfo(nullptr);
     }
-    mOpener = nullptr;
 
-    // false as the last parameter so that xul:iframe/browser/editor
-    // session history handling works like dynamic html:iframes.
-    // Usually xul elements are used in chrome, which doesn't have
-    // session history at all.
-    mFrameLoader = nsFrameLoader::Create(this, opener, false);
+    // false as the networkCreated parameter so that xul:iframe/browser/editor
+    // session history handling works like dynamic html:iframes. Usually xul
+    // elements are used in chrome, which doesn't have session history at all.
+    mFrameLoader = nsFrameLoader::Create(this, false, openWindowInfo);
     if (NS_WARN_IF(!mFrameLoader)) {
       return;
     }