diff --git a/src/slic3r/GUI/Plater.cpp b/src/slic3r/GUI/Plater.cpp
index 04fe7026f7..26b9217b3f 100644
--- a/src/slic3r/GUI/Plater.cpp
+++ b/src/slic3r/GUI/Plater.cpp
@@ -8959,7 +8959,14 @@ void Plater::priv::reload_from_disk()
                 if (has_source && old_volume->source.object_idx < int(new_model.objects.size())) {
                     const ModelObject *obj = new_model.objects[old_volume->source.object_idx];
                     if (old_volume->source.volume_idx < int(obj->volumes.size())) {
-                        if (obj->volumes[old_volume->source.volume_idx]->source.input_file == old_volume->source.input_file) {
+                        const std::string &new_input_file = obj->volumes[old_volume->source.volume_idx]->source.input_file;
+                        const std::string &old_input_file = old_volume->source.input_file;
+                        // Orca: match on the exact source path first, then fall back to filename-only so reload
+                        // still matches when the project stored a bare filename and the file was found next to
+                        // the project (same-folder fallback) or picked via the locate dialog (#12992).
+                        if (new_input_file == old_input_file ||
+                            boost::algorithm::iequals(fs::path(new_input_file).filename().string(),
+                                                      fs::path(old_input_file).filename().string())) {
                             new_volume_idx = old_volume->source.volume_idx;
                             new_object_idx = old_volume->source.object_idx;
                             match_found    = true;
diff --git a/src/slic3r/GUI/Preferences.cpp b/src/slic3r/GUI/Preferences.cpp
index b0aba418dc..af7522c33d 100644
--- a/src/slic3r/GUI/Preferences.cpp
+++ b/src/slic3r/GUI/Preferences.cpp
@@ -1664,6 +1664,13 @@ void PreferencesDialog::create_items()
     );
     g_sizer->Add(item_draco_bits);
 
+    auto item_full_source_paths = create_item_checkbox(_L("Store full source file paths in projects"),
+        _L("If enabled, saved projects store the absolute path to imported source files (STEP/STL/...), so "
+           "\"Reload from disk\" still works when the source file is kept in a different folder than the project. "
+           "If disabled, only the filename is stored, which keeps projects portable and avoids embedding absolute paths."),
+        "export_sources_full_pathnames");
+    g_sizer->Add(item_full_source_paths);
+
     //// GENERAL > Preset
     g_sizer->Add(create_item_title(_L("Preset")), 1, wxEXPAND);