Index: generic/nsf.c
===================================================================
diff -u -r6028c95c4c4f96815c25ab8dc9760ab2a2dd901b -r7312bac146d4f5bf1d2a9655def3c4dc09dbe435
--- generic/nsf.c	(.../nsf.c)	(revision 6028c95c4c4f96815c25ab8dc9760ab2a2dd901b)
+++ generic/nsf.c	(.../nsf.c)	(revision 7312bac146d4f5bf1d2a9655def3c4dc09dbe435)
@@ -5706,8 +5706,11 @@
         GetVarAndNameFromHash(entryPtr, &varPtr, &nameObj);
         VarHashRefCount(varPtr)++;
         if ((varPtr->flags & VAR_TRACED_UNSET) != 0u /* TclIsVarTraced(varPtr) */) {
+
           (void)UnsetInstVar(interp, 1 /* no error msg */, object, ObjStr(nameObj));
 
+          /* The variable might have been brought back by an unset trace, plus
+             newly created unset traces; deactivate *all* traces on revived vars. */
           if (TclIsVarTraced(varPtr)) {
             Tcl_HashEntry *tPtr = Tcl_FindHashEntry(&iPtr->varTraces, varPtr);
             VarTrace *tracePtr = Tcl_GetHashValue(tPtr);
@@ -5735,7 +5738,6 @@
     }
 }
 
-
 /*
  *----------------------------------------------------------------------
  * NSCleanupNamespace --