Initial raw liboverride-dedicated view in the Outliner.

Disclaimer: this is merely a copy of the Libraries (aka blend file)
view, with some minor tweaking.

release/scripts/startup/bl_ui/space_outliner.py

@@ -51,13 +51,13 @@ class OUTLINER_HT_header(Header):
             row.prop(space, "use_sync_select", icon='UV_SYNC_SELECT', text="")
 
         row = layout.row(align=True)
-        if display_mode in {'SCENES', 'VIEW_LAYER'}:
+        if display_mode in {'SCENES', 'VIEW_LAYER', 'LIBRARY_OVERRIDES'}:
             row.popover(
                 panel="OUTLINER_PT_filter",
                 text="",
                 icon='FILTER',
             )
-        elif display_mode in {'LIBRARIES', 'ORPHAN_DATA'}:
+        if display_mode in {'LIBRARIES', 'LIBRARY_OVERRIDES', 'ORPHAN_DATA'}:
             row.prop(space, "use_filter_id_type", text="", icon='FILTER')
             sub = row.row(align=True)
             sub.active = space.use_filter_id_type
@@ -341,19 +341,26 @@ class OUTLINER_PT_filter(Panel):
             col = layout.column(align=True)
             col.prop(space, "use_sort_alpha")
 
-        row = layout.row(align=True)
-        row.prop(space, "use_sync_select", text="Sync Selection")
+        if display_mode not in {'LIBRARY_OVERRIDES'}:
+            row = layout.row(align=True)
+            row.prop(space, "use_sync_select", text="Sync Selection")
 
-        row = layout.row(align=True)
-        row.prop(space, "show_mode_column", text="Show Mode Column")
-        layout.separator()
+            row = layout.row(align=True)
+            row.prop(space, "show_mode_column", text="Show Mode Column")
+            layout.separator()
 
         col = layout.column(align=True)
         col.label(text="Search")
         col.prop(space, "use_filter_complete", text="Exact Match")
         col.prop(space, "use_filter_case_sensitive", text="Case Sensitive")
 
-        if display_mode != 'VIEW_LAYER':
+        if display_mode in {'LIBRARY_OVERRIDES'} and bpy.data.libraries:
+            col.separator()
+            row = col.row()
+            row.label(icon='LIBRARY_DATA_OVERRIDE')
+            row.prop(space, "use_filter_lib_override_system", text="System Overrides")
+
+        if display_mode not in {'VIEW_LAYER'}:
             return
 
         layout.separator()
@@ -405,10 +412,6 @@ class OUTLINER_PT_filter(Panel):
         row = sub.row()
         row.label(icon='EMPTY_DATA')
         row.prop(space, "use_filter_object_empty", text="Empties")
-        row = sub.row()
-        if bpy.data.libraries:
-            row.label(icon='LIBRARY_DATA_OVERRIDE')
-            row.prop(space, "use_filter_lib_override", text="Library Overrides")
 
         if (
                 bpy.data.curves or
@@ -425,6 +428,16 @@ class OUTLINER_PT_filter(Panel):
             row.label(icon='BLANK1')
             row.prop(space, "use_filter_object_others", text="Others")
 
+        if bpy.data.libraries:
+            col.separator()
+            row = col.row()
+            row.label(icon='LIBRARY_DATA_OVERRIDE')
+            row.prop(space, "use_filter_lib_override", text="Library Overrides")
+            row = col.row()
+            row.label(icon='LIBRARY_DATA_OVERRIDE')
+            row.prop(space, "use_filter_lib_override_system", text="System Overrides")
+
+
 
 classes = (
     OUTLINER_HT_header,

source/blender/blenkernel/intern/lib_override.c

@@ -702,6 +702,9 @@ static void lib_override_library_create_post_process(Main *bmain,
                 base = BKE_view_layer_base_find(view_layer, ob_new);
                 DEG_id_tag_update_ex(
                     bmain, &ob_new->id, ID_RECALC_TRANSFORM | ID_RECALC_BASE_FLAGS);
+                if (is_resync) {
+                  ob_new->id.flag |= LIB_LIB_OVERRIDE_RESYNC_LEFTOVER;
+                }
               }
 
               if (ob_new == (Object *)ob_reference->id.newid && base != NULL) {
@@ -713,6 +716,9 @@ static void lib_override_library_create_post_process(Main *bmain,
                          view_layer, ob_new, is_resync)) {
               BKE_collection_object_add(bmain, collection_new, ob_new);
               DEG_id_tag_update_ex(bmain, &ob_new->id, ID_RECALC_TRANSFORM | ID_RECALC_BASE_FLAGS);
+              if (is_resync) {
+                ob_new->id.flag |= LIB_LIB_OVERRIDE_RESYNC_LEFTOVER;
+              }
             }
           }
         }
@@ -729,6 +735,9 @@ static void lib_override_library_create_post_process(Main *bmain,
           else {
             BKE_collection_object_add_from(bmain, scene, (Object *)id_root, ob_new);
           }
+          if (is_resync) {
+            ob_new->id.flag |= LIB_LIB_OVERRIDE_RESYNC_LEFTOVER;
+          }
         }
         break;
       }
@@ -1071,6 +1080,7 @@ bool BKE_lib_override_library_resync(Main *bmain,
         /* Otherwise, keep them, user needs to decide whether what to do with them. */
         BLI_assert((id->tag & LIB_TAG_DOIT) == 0);
         id_fake_user_set(id);
+        id->flag |= LIB_LIB_OVERRIDE_RESYNC_LEFTOVER;
         CLOG_INFO(&LOG, 2, "Old override %s is being kept around as it was user-edited", id->name);
       }
     }

source/blender/editors/space_outliner/CMakeLists.txt

@@ -51,6 +51,7 @@ set(SRC
   tree/tree_display_data.cc
   tree/tree_display_libraries.cc
   tree/tree_display_orphaned.cc
+  tree/tree_display_override_library.cc
   tree/tree_display_scenes.cc
   tree/tree_display_sequencer.cc
   tree/tree_display_view_layer.cc

source/blender/editors/space_outliner/outliner_collections.c

@@ -166,8 +166,11 @@ void ED_outliner_selected_objects_get(const bContext *C, ListBase *objects)
 bool ED_outliner_collections_editor_poll(bContext *C)
 {
   SpaceOutliner *space_outliner = CTX_wm_space_outliner(C);
-  return (space_outliner != NULL) &&
-         ELEM(space_outliner->outlinevis, SO_VIEW_LAYER, SO_SCENES, SO_LIBRARIES);
+  return (space_outliner != NULL) && ELEM(space_outliner->outlinevis,
+                                          SO_VIEW_LAYER,
+                                          SO_SCENES,
+                                          SO_LIBRARIES,
+                                          SO_OVERRIDES_LIBRARY);
 }
 
 static bool outliner_view_layer_collections_editor_poll(bContext *C)

source/blender/editors/space_outliner/outliner_draw.c

@@ -1775,6 +1775,116 @@ static void outliner_draw_userbuts(uiBlock *block,
   }
 }
 
+static bool outliner_draw_overrides_buts(uiBlock *block,
+                                         ARegion *region,
+                                         SpaceOutliner *space_outliner,
+                                         ListBase *lb,
+                                         const bool is_open)
+{
+  bool parent_has_warnings = false;
+
+  LISTBASE_FOREACH (TreeElement *, te, lb) {
+    bool has_warnings = false;
+    const bool do_draw = (te->ys + 2 * UI_UNIT_Y >= region->v2d.cur.ymin &&
+                          te->ys <= region->v2d.cur.ymax);
+    int but_flag = UI_BUT_DRAG_LOCK;
+    const char *tip = NULL;
+
+    TreeStoreElem *tselem = TREESTORE(te);
+    switch (tselem->type) {
+      case TSE_SOME_ID: {
+#if 0
+        if (id->flag & LIB_FAKEUSER) {
+          tip = TIP_("Data-block will be retained using a fake user");
+        }
+        else {
+          tip = TIP_("Data-block has no users and will be deleted");
+        }
+        bt = uiDefIconButBitS(block,
+                              UI_BTYPE_ICON_TOGGLE,
+                              LIB_FAKEUSER,
+                              1,
+                              ICON_FAKE_USER_OFF,
+                              (int)(region->v2d.cur.xmax - OL_TOG_USER_BUTS_STATUS),
+                              te->ys,
+                              UI_UNIT_X,
+                              UI_UNIT_Y,
+                              &id->flag,
+                              0,
+                              0,
+                              0,
+                              0,
+                              tip);
+        UI_but_func_set(bt, restrictbutton_id_user_toggle, id, NULL);
+        UI_but_flag_enable(bt, but_flag);
+#endif
+        break;
+      }
+      case TSE_LIBRARY_OVERRIDE_BASE: {
+        ID *id = tselem->id;
+
+        if (ID_IS_OVERRIDE_LIBRARY_REAL(id) && ID_REAL_USERS(id) == 0) {
+          has_warnings = true;
+          if (do_draw) {
+            tip = TIP_("This override data-block is unused");
+          }
+        }
+
+        else if (id->flag & LIB_LIB_OVERRIDE_RESYNC_LEFTOVER) {
+          has_warnings = true;
+          if (do_draw) {
+            tip = TIP_(
+                "This override data-block is not needed anymore, but was detected as user-edited");
+          }
+        }
+        break;
+      }
+      case TSE_LIBRARY_OVERRIDE: {
+        const bool is_rna_path_valid = (bool)(POINTER_AS_UINT(te->directdata));
+        if (!is_rna_path_valid) {
+          has_warnings = true;
+          if (do_draw) {
+            tip = TIP_(
+                "This override property does not exist in current data, it will be removed on "
+                "next .blend file save");
+          }
+        }
+        break;
+      }
+      default:
+        break;
+    }
+
+    const bool have_children_warnings = outliner_draw_overrides_buts(
+        block,
+        region,
+        space_outliner,
+        &te->subtree,
+        is_open && TSELEM_OPEN(tselem, space_outliner));
+
+    if (do_draw &&
+        (has_warnings || (have_children_warnings && !TSELEM_OPEN(tselem, space_outliner)))) {
+      if (tip == NULL) {
+        tip = TIP_("Some sub-items require attention");
+      }
+      uiBut *bt = uiDefIconBlockBut(block,
+                                    NULL,
+                                    NULL,
+                                    1,
+                                    ICON_ERROR,
+                                    (int)(region->v2d.cur.xmax - OL_TOG_USER_BUTS_STATUS),
+                                    te->ys,
+                                    UI_UNIT_X,
+                                    UI_UNIT_Y,
+                                    tip);
+      UI_but_flag_enable(bt, but_flag);
+    }
+    parent_has_warnings = parent_has_warnings || has_warnings || have_children_warnings;
+  }
+
+  return parent_has_warnings;
+}
+
 static void outliner_draw_rnacols(ARegion *region, int sizex)
 {
   View2D *v2d = &region->v2d;
@@ -2896,7 +3006,19 @@ static void outliner_draw_iconrow(bContext *C,
         active = tree_element_type_active_state_get(C, tvc, te, tselem);
       }
 
-      if (!ELEM(tselem->type, TSE_SOME_ID, TSE_LAYER_COLLECTION, TSE_R_LAYER, TSE_GP_LAYER)) {
+      if (!ELEM(tselem->type,
+                TSE_ID_BASE,
+                TSE_SOME_ID,
+                TSE_LAYER_COLLECTION,
+                TSE_R_LAYER,
+                TSE_GP_LAYER,
+                TSE_LIBRARY_OVERRIDE_BASE,
+                TSE_LIBRARY_OVERRIDE,
+                TSE_BONE,
+                TSE_EBONE,
+                TSE_POSE_CHANNEL,
+                TSE_POSEGRP,
+                TSE_DEFGROUP)) {
         outliner_draw_iconrow_doit(block, te, fstyle, xmax, offsx, ys, alpha_fac, active, 1);
       }
       else {
@@ -3656,7 +3778,11 @@ void draw_outliner(const bContext *C)
   }
 
   /* Sync selection state from view layer. */
-  if (!ELEM(space_outliner->outlinevis, SO_LIBRARIES, SO_DATA_API, SO_ID_ORPHANS) &&
+  if (!ELEM(space_outliner->outlinevis,
+            SO_LIBRARIES,
+            SO_OVERRIDES_LIBRARY,
+            SO_DATA_API,
+            SO_ID_ORPHANS) &&
       space_outliner->flag & SO_SYNC_SELECT) {
     outliner_sync_selection(C, space_outliner);
   }
@@ -3703,6 +3829,10 @@ void draw_outliner(const bContext *C)
     /* draw user toggle columns */
     outliner_draw_userbuts(block, region, space_outliner, &space_outliner->tree);
   }
+  else if (space_outliner->outlinevis == SO_OVERRIDES_LIBRARY) {
+    /* Draw overrides status columns. */
+    outliner_draw_overrides_buts(block, region, space_outliner, &space_outliner->tree, true);
+  }
   else if (restrict_column_width > 0.0f) {
     /* draw restriction columns */
     RestrictPropertiesActive props_active;

source/blender/editors/space_outliner/outliner_intern.h

@@ -193,7 +193,7 @@ typedef enum {
 /* The outliner display modes that support the filter system.
  * Note: keep it synced with space_outliner.py */
 #define SUPPORT_FILTER_OUTLINER(space_outliner_) \
-  (ELEM((space_outliner_)->outlinevis, SO_VIEW_LAYER))
+  (ELEM((space_outliner_)->outlinevis, SO_VIEW_LAYER, SO_OVERRIDES_LIBRARY))
 
 /* Outliner Searching --
  *

source/blender/editors/space_outliner/outliner_sync.c

@@ -356,8 +356,11 @@ static void outliner_sync_selection_from_outliner(Scene *scene,
 void ED_outliner_select_sync_from_outliner(bContext *C, SpaceOutliner *space_outliner)
 {
   /* Don't sync if not checked or in certain outliner display modes */
-  if (!(space_outliner->flag & SO_SYNC_SELECT) ||
-      ELEM(space_outliner->outlinevis, SO_LIBRARIES, SO_DATA_API, SO_ID_ORPHANS)) {
+  if (!(space_outliner->flag & SO_SYNC_SELECT) || ELEM(space_outliner->outlinevis,
+                                                       SO_LIBRARIES,
+                                                       SO_OVERRIDES_LIBRARY,
+                                                       SO_DATA_API,
+                                                       SO_ID_ORPHANS)) {
     return;
   }
 

source/blender/editors/space_outliner/outliner_tree.c

@@ -908,6 +908,11 @@ TreeElement *outliner_add_element(SpaceOutliner *space_outliner,
       BLI_assert(!"Expected this ID type to be ported to new Outliner tree-element design");
     }
   }
+  else if (ELEM(type, TSE_LIBRARY_OVERRIDE_BASE, TSE_LIBRARY_OVERRIDE)) {
+    if (!te->type) {
+      BLI_assert(!"Expected override types to be ported to new Outliner tree-element design");
+    }
+  }
   else {
     /* Other cases must be caught above. */
     BLI_assert(TSE_IS_REAL_ID(tselem));

source/blender/editors/space_outliner/outliner_utils.c

@@ -361,6 +361,7 @@ float outliner_restrict_columns_width(const SpaceOutliner *space_outliner)
     case SO_DATA_API:
     case SO_SEQUENCE:
     case SO_LIBRARIES:
+    case SO_OVERRIDES_LIBRARY:
       return 0.0f;
     case SO_ID_ORPHANS:
       num_columns = 3;

source/blender/editors/space_outliner/space_outliner.c

@@ -273,7 +273,7 @@ static void outliner_main_region_message_subscribe(const wmRegionMessageSubscrib
       .notify = ED_region_do_msg_notify_tag_redraw,
   };
 
-  if (ELEM(space_outliner->outlinevis, SO_VIEW_LAYER, SO_SCENES)) {
+  if (ELEM(space_outliner->outlinevis, SO_VIEW_LAYER, SO_SCENES, SO_OVERRIDES_LIBRARY)) {
     WM_msg_subscribe_rna_anon_prop(mbus, Window, view_layer, &msg_sub_value_region_tag_redraw);
   }
 }

source/blender/editors/space_outliner/tree/tree_display.cc

@@ -44,6 +44,9 @@ TreeDisplay *outliner_tree_display_create(eSpaceOutliner_Mode mode, SpaceOutline
     case SO_ID_ORPHANS:
       tree_display = new TreeDisplayIDOrphans(*space_outliner);
       break;
+    case SO_OVERRIDES_LIBRARY:
+      tree_display = new TreeDisplayOverrideLibrary(*space_outliner);
+      break;
     case SO_VIEW_LAYER:
     default:
       tree_display = new TreeDisplayViewLayer(*space_outliner);

source/blender/editors/space_outliner/tree/tree_display.hh

@@ -110,6 +110,24 @@ class TreeDisplayLibraries final : public AbstractTreeDisplay {
   short id_filter_get() const;
 };
 
+/* -------------------------------------------------------------------- */
+/* Library Overrides Tree-Display. */
+
+/**
+ * \brief Tree-Display for the Library Overrides display mode.
+ */
+class TreeDisplayOverrideLibrary final : public AbstractTreeDisplay {
+ public:
+  TreeDisplayOverrideLibrary(SpaceOutliner &space_outliner);
+
+  ListBase buildTree(const TreeSourceData &source_data) override;
+
+ private:
+  TreeElement *add_library_contents(Main &, ListBase &, Library *) const;
+  bool override_library_id_filter_poll(Library *lib, ID *id) const;
+  short id_filter_get() const;
+};
+
 /* -------------------------------------------------------------------- */
 /* Video Sequencer Tree-Display */
 

source/blender/editors/space_outliner/tree/tree_display_override_library.cc

@@ -0,0 +1,204 @@
+/*
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation; either version 2
+ * of the License, or (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software Foundation,
+ * Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
+ */
+
+/** \file
+ * \ingroup spoutliner
+ */
+
+#include "BLI_listbase.h"
+#include "BLI_listbase_wrapper.hh"
+
+#include "BKE_collection.h"
+#include "BKE_main.h"
+
+#include "DNA_collection_types.h"
+
+#include "BLT_translation.h"
+
+#include "../outliner_intern.h"
+#include "tree_display.hh"
+
+namespace blender::ed::outliner {
+
+/* Convenience/readability. */
+template<typename T> using List = ListBaseWrapper<T>;
+
+TreeDisplayOverrideLibrary::TreeDisplayOverrideLibrary(SpaceOutliner &space_outliner)
+    : AbstractTreeDisplay(space_outliner)
+{
+}
+
+ListBase TreeDisplayOverrideLibrary::buildTree(const TreeSourceData &source_data)
+{
+  ListBase tree = {nullptr};
+
+  {
+    /* current file first - mainvar provides tselem with unique pointer - not used */
+    TreeElement *ten = add_library_contents(*source_data.bmain, tree, nullptr);
+    TreeStoreElem *tselem;
+
+    if (ten) {
+      tselem = TREESTORE(ten);
+      if (!tselem->used) {
+        tselem->flag &= ~TSE_CLOSED;
+      }
+    }
+  }
+
+  for (ID *id : List<ID>(source_data.bmain->libraries)) {
+    Library *lib = reinterpret_cast<Library *>(id);
+    TreeElement *ten = add_library_contents(*source_data.bmain, tree, lib);
+    /* NULL-check matters, due to filtering there may not be a new element. */
+    if (ten) {
+      lib->id.newid = (ID *)ten;
+    }
+  }
+
+  /* make hierarchy */
+  for (TreeElement *ten : List<TreeElement>(tree)) {
+    if (ten == tree.first) {
+      /* First item is main, skip. */
+      continue;
+    }
+
+    TreeStoreElem *tselem = TREESTORE(ten);
+    Library *lib = (Library *)tselem->id;
+    BLI_assert(!lib || (GS(lib->id.name) == ID_LI));
+    if (!lib || !lib->parent) {
+      continue;
+    }
+
+    TreeElement *parent = (TreeElement *)lib->parent->id.newid;
+
+    if (tselem->id->tag & LIB_TAG_INDIRECT) {
+      /* Only remove from 'first level' if lib is not also directly used. */
+      BLI_remlink(&tree, ten);
+      BLI_addtail(&parent->subtree, ten);
+      ten->parent = parent;
+    }
+    else {
+      /* Else, make a new copy of the libtree for our parent. */
+      TreeElement *dupten = add_library_contents(*source_data.bmain, parent->subtree, lib);
+      if (dupten) {
+        dupten->parent = parent;
+      }
+    }
+  }
+  /* restore newid pointers */
+  for (ID *library_id : List<ID>(source_data.bmain->libraries)) {
+    library_id->newid = nullptr;
+  }
+
+  return tree;
+}
+
+TreeElement *TreeDisplayOverrideLibrary::add_library_contents(Main &mainvar,
+                                                              ListBase &lb,
+                                                              Library *lib) const
+{
+  const short filter_id_type = id_filter_get();
+
+  ListBase *lbarray[INDEX_ID_MAX];
+  int tot;
+  if (filter_id_type) {
+    lbarray[0] = which_libbase(&mainvar, space_outliner_.filter_id_type);
+    tot = 1;
+  }
+  else {
+    tot = set_listbasepointers(&mainvar, lbarray);
+  }
+
+  TreeElement *tenlib = nullptr;
+  for (int a = 0; a < tot; a++) {
+    if (!lbarray[a] || !lbarray[a]->first) {
+      continue;
+    }
+
+    ID *id = nullptr;
+
+    /* check if there's data in current lib */
+    for (ID *id_iter : List<ID>(lbarray[a])) {
+      if (id_iter->lib == lib && ID_IS_OVERRIDE_LIBRARY_REAL(id_iter)) {
+        id = id_iter;
+        break;
+      }
+    }
+
+    if (id != nullptr) {
+      if (!tenlib) {
+        /* Create library tree element on demand, depending if there are any data-blocks. */
+        if (lib) {
+          tenlib = outliner_add_element(&space_outliner_, &lb, lib, nullptr, TSE_SOME_ID, 0);
+        }
+        else {
+          tenlib = outliner_add_element(&space_outliner_, &lb, &mainvar, nullptr, TSE_ID_BASE, 0);
+          tenlib->name = IFACE_("Current File");
+        }
+      }
+
+      /* Create data-block list parent element on demand. */
+      if (id != nullptr) {
+        TreeElement *ten;
+
+        if (filter_id_type) {
+          ten = tenlib;
+        }
+        else {
+          ten = outliner_add_element(
+              &space_outliner_, &tenlib->subtree, lbarray[a], nullptr, TSE_ID_BASE, 0);
+          ten->directdata = lbarray[a];
+          ten->name = outliner_idcode_to_plural(GS(id->name));
+        }
+
+        for (ID *id : List<ID>(lbarray[a])) {
+          if (override_library_id_filter_poll(lib, id)) {
+            TreeElement *override_tree_element = outliner_add_element(
+                &space_outliner_, &ten->subtree, id, ten, TSE_LIBRARY_OVERRIDE_BASE, 0);
+
+            if (BLI_listbase_is_empty(&override_tree_element->subtree)) {
+              outliner_free_tree_element(override_tree_element, &ten->subtree);
+            }
+          }
+        }
+      }
+    }
+  }
+
+  return tenlib;
+}
+
+short TreeDisplayOverrideLibrary::id_filter_get() const
+{
+  if (space_outliner_.filter & SO_FILTER_ID_TYPE) {
+    return space_outliner_.filter_id_type;
+  }
+  return 0;
+}
+
+bool TreeDisplayOverrideLibrary::override_library_id_filter_poll(Library *lib, ID *id) const
+{
+  if (id->lib != lib) {
+    return false;
+  }
+
+  if (!ID_IS_OVERRIDE_LIBRARY_REAL(id)) {
+    return false;
+  }
+
+  return true;
+}
+
+}  // namespace blender::ed::outliner

source/blender/editors/space_outliner/tree/tree_element_overrides.cc

@@ -40,13 +40,24 @@ TreeElementOverridesBase::TreeElementOverridesBase(TreeElement &legacy_te, ID &i
     : AbstractTreeElement(legacy_te), id_(id)
 {
   BLI_assert(legacy_te.store_elem->type == TSE_LIBRARY_OVERRIDE_BASE);
-  legacy_te.name = IFACE_("Library Overrides");
+  if (legacy_te.parent != nullptr &&
+      ELEM(legacy_te.parent->store_elem->type, TSE_SOME_ID, TSE_LAYER_COLLECTION))
+
+  {
+    legacy_te.name = IFACE_("Library Overrides");
+  }
+  else {
+    legacy_te.name = id.name + 2;
+  }
 }
 
 void TreeElementOverridesBase::expand(SpaceOutliner &space_outliner) const
 {
   BLI_assert(id_.override_library != nullptr);
 
+  const bool show_system_overrides = (SUPPORT_FILTER_OUTLINER(&space_outliner) &&
+                                      (space_outliner.filter & SO_FILTER_SHOW_SYSTEM_OVERRIDES) !=
+                                          0);
   PointerRNA idpoin;
   RNA_id_pointer_create(&id_, &idpoin);
 
@@ -56,15 +67,26 @@ void TreeElementOverridesBase::expand(SpaceOutliner &space_outliner) const
 
   for (auto *override_prop :
        ListBaseWrapper<IDOverrideLibraryProperty>(id_.override_library->properties)) {
-    if (!BKE_lib_override_rna_property_find(
-            &idpoin, override_prop, &override_rna_ptr, &override_rna_prop)) {
-      /* This is fine, override properties list is not always fully up-to-date with current
-       * RNA/IDProps etc., this gets cleaned up when re-generating the overrides rules,
-       * no error here. */
-      continue;
+    const bool is_rna_path_valid = BKE_lib_override_rna_property_find(
+        &idpoin, override_prop, &override_rna_ptr, &override_rna_prop);
+    if (is_rna_path_valid && !show_system_overrides &&
+        ELEM(override_prop->rna_prop_type, PROP_POINTER, PROP_COLLECTION) &&
+        RNA_struct_is_ID(RNA_property_pointer_type(&override_rna_ptr, override_rna_prop))) {
+      bool do_continue = true;
+      for (auto *override_prop_op :
+           ListBaseWrapper<IDOverrideLibraryPropertyOperation>(override_prop->operations)) {
+        if ((override_prop_op->flag & IDOVERRIDE_LIBRARY_FLAG_IDPOINTER_MATCH_REFERENCE) == 0) {
+          do_continue = false;
+          break;
+        }
+      }
+
+      if (do_continue) {
+        continue;
+      }
     }
 
-    TreeElementOverridesData data = {id_, *override_prop};
+    TreeElementOverridesData data = {id_, *override_prop, is_rna_path_valid};
     outliner_add_element(
         &space_outliner, &legacy_te_.subtree, &data, &legacy_te_, TSE_LIBRARY_OVERRIDE, index++);
   }
@@ -79,6 +101,9 @@ TreeElementOverridesProperty::TreeElementOverridesProperty(TreeElement &legacy_t
   BLI_assert(legacy_te.store_elem->type == TSE_LIBRARY_OVERRIDE);
 
   legacy_te.name = override_prop_.rna_path;
+  /* Abusing this for now, better way to do it is also pending current refacor of the whole tree
+   * code to use CPP... */
+  legacy_te.directdata = POINTER_FROM_UINT(override_data.is_rna_path_valid);
 }
 
 }  // namespace blender::ed::outliner

source/blender/editors/space_outliner/tree/tree_element_overrides.hh

@@ -27,6 +27,7 @@ namespace blender::ed::outliner {
 struct TreeElementOverridesData {
   ID &id;
   IDOverrideLibraryProperty &override_property;
+  bool is_rna_path_valid;
 };
 
 class TreeElementOverridesBase final : public AbstractTreeElement {

source/blender/makesdna/DNA_ID.h

@@ -491,6 +491,11 @@ enum {
    * Note that this also applies to shapekeys, even though they are not 100% embedded data...
    */
   LIB_EMBEDDED_DATA_LIB_OVERRIDE = 1 << 12,
+  /**
+   * The override data-block appears to not be needed anymore after resync with linked data, but it
+   * was kept around (because e.g. detected as user-edited).
+   */
+  LIB_LIB_OVERRIDE_RESYNC_LEFTOVER = 1 << 13,
 };
 
 /**

source/blender/makesdna/DNA_space_types.h

@@ -323,6 +323,8 @@ typedef enum eSpaceOutliner_Filter {
   SO_FILTER_NO_CHILDREN = (1 << 4),
 
   SO_FILTER_UNUSED_5 = (1 << 5), /* cleared */
+  /** Show overrides that are defined/controlled by Blender. */
+  SO_FILTER_SHOW_SYSTEM_OVERRIDES = SO_FILTER_UNUSED_5, /* re-use */
   SO_FILTER_NO_OB_MESH = (1 << 6),
   SO_FILTER_NO_OB_ARMATURE = (1 << 7),
   SO_FILTER_NO_OB_EMPTY = (1 << 8),
@@ -391,6 +393,7 @@ typedef enum eSpaceOutliner_Mode {
   /* SO_KEYMAP         = 13, */ /* deprecated! */
   SO_ID_ORPHANS = 14,
   SO_VIEW_LAYER = 15,
+  SO_OVERRIDES_LIBRARY = 16,
 } eSpaceOutliner_Mode;
 
 /* SpaceOutliner.storeflag */

source/blender/makesrna/intern/rna_space.c

@@ -3399,6 +3399,11 @@ static void rna_def_space_outliner(BlenderRNA *brna)
        ICON_RNA,
        "Data API",
        "Display low level Blender data and its properties"},
+      {SO_OVERRIDES_LIBRARY,
+       "LIBRARY_OVERRIDES",
+       ICON_LIBRARY_DATA_OVERRIDE,
+       "Library Overrides",
+       "Display library overrides data-blocks"},
       {SO_ID_ORPHANS,
        "ORPHAN_DATA",
        ICON_ORPHAN_DATA,
@@ -3588,6 +3593,14 @@ static void rna_def_space_outliner(BlenderRNA *brna)
                            "Show Library Overrides",
                            "For libraries with overrides created, show the overridden values");
   RNA_def_property_update(prop, NC_SPACE | ND_SPACE_OUTLINER, NULL);
+
+  prop = RNA_def_property(srna, "use_filter_lib_override_system", PROP_BOOLEAN, PROP_NONE);
+  RNA_def_property_boolean_sdna(prop, NULL, "filter", SO_FILTER_SHOW_SYSTEM_OVERRIDES);
+  RNA_def_property_ui_text(prop,
+                           "Show System Overrides",
+                           "For libraries with overrides created, show the overridden values that "
+                           "are defined/controlled by Blender");
+  RNA_def_property_update(prop, NC_SPACE | ND_SPACE_OUTLINER, NULL);
 }
 
 static void rna_def_space_view3d_shading(BlenderRNA *brna)