`NDEBUG_PERSIST_TILL_NEXT_SERVER` is *supposed* to make debug overlays only persist until the next time the edit interface is drawn again. However, the duration is too long and causes the debug overlays to overlap several times.

Adding a debug ConVar (e.g., `nav_overlay_duration_test`) and replacing the line with:

    const float DebugDuration = nav_overlay_duration_test.GetBool() ? NDEBUG_PERSIST_TILL_NEXT_SERVER : 0.0f;

And then toggling the value of `nav_overlay_duration_test` will show exactly what I mean, in addition, the edit interface flickers because of this bug.