diff --git a/TODO b/TODO
index 58e8e3d..e425342 100644
--- a/TODO
+++ b/TODO
@@ -36,11 +36,17 @@ General
    and why they're there.  Maybe they're objects that used to be
    stream lengths.  Probably we just need to make sure don't traverse
    through a stream's /Length stream when enqueueing stream
-   dictionaries.
+   dictionaries.  This could potentially happen with any object that
+   QPDFWriter replaces when writing out files.  Such objects would be
+   orphaned in the newly written file.  This could be fixed, but it
+   may not be worth fixing.
 
    If flattenScalarReferences is removed, a new method will be needed
    for checking PDF files.
 
+ * See if we can avoid preserving unreferenced objects in objet
+   streams even when preserving the object streams.
+
  * For debugging linearization bugs, consider adding an option to save
    pass 1 of linearization.  This code is sufficient.  Change the
    interface to allow specification of a pass1 file, which would