--- a/netwerk/protocol/http/nsHttpConnectionMgr.cpp
+++ b/netwerk/protocol/http/nsHttpConnectionMgr.cpp
@@ -4586,20 +4586,21 @@ nsHalfOpenSocket::SetFastOpenConnected(n
     // in case nsHttpConnection::Activate fails will be done in StartFastOpen.
     // Also OnMsgReclaimConnection can decided that we do not need this
     // transaction and cancel it as well.
     // In all other cases mConnectionNegotiatingFastOpen must not be nullptr.
     if (!mConnectionNegotiatingFastOpen) {
         return;
     }
 
-    MOZ_ASSERT((mFastOpenStatus == TFO_NOT_TRIED) || 
+    MOZ_ASSERT((mFastOpenStatus == TFO_NOT_TRIED) ||
                (mFastOpenStatus == TFO_DATA_SENT) ||
                (mFastOpenStatus == TFO_TRIED) ||
-               (mFastOpenStatus == TFO_DATA_COOKIE_NOT_ACCEPTED));
+               (mFastOpenStatus == TFO_DATA_COOKIE_NOT_ACCEPTED) ||
+               (mFastOpenStatus == TFO_DISABLED));
 
     RefPtr<nsHalfOpenSocket> deleteProtector(this);
 
     mEnt->mDoNotDestroy = true;
 
     // Delete 2 points of entry to FastOpen function so that we do not reenter.
     mEnt->mHalfOpenFastOpenBackups.RemoveElement(this);
     mSocketTransport->SetFastOpenCallback(nullptr);