diff --git a/apps/opencs/model/world/data.cpp b/apps/opencs/model/world/data.cpp
index 4fd3939883..3ac499b4f4 100644
--- a/apps/opencs/model/world/data.cpp
+++ b/apps/opencs/model/world/data.cpp
@@ -991,8 +991,6 @@ int CSMWorld::Data::startLoading (const std::filesystem::path& path, bool base,
     mReader->setIndex((project || !base) ? 0 : mReaderIndex++);
     mReader->open (path);
 
-    mContentFileNames.insert(std::make_pair(path.filename().string(), mReader->getIndex())); //TODO(Project579): let's hope unicode characters are never used in these filenames on windows or this will break
-
     mBase = base;
     mProject = project;
 
diff --git a/apps/opencs/model/world/data.hpp b/apps/opencs/model/world/data.hpp
index 2764daa8aa..112ac1b239 100644
--- a/apps/opencs/model/world/data.hpp
+++ b/apps/opencs/model/world/data.hpp
@@ -126,8 +126,6 @@ namespace CSMWorld
 
             std::vector<std::shared_ptr<ESM::ESMReader> > mReaders;
 
-            std::map<std::string, int> mContentFileNames;
-
             // not implemented
             Data (const Data&);
             Data& operator= (const Data&);