Collections: Add color tagging & use in outliner

Add a color tag to collections and allow tagging from the outliner
context menu.

Show the colored icon in UI menus.

34 files changed, 451 insertions, 190 deletions

diff --git a/release/datafiles/userdef/userdef_default_theme.c b/release/datafiles/userdef/userdef_default_theme.c
index 4d48bb8eaac..1fbde066ef6 100644
--- a/release/datafiles/userdef/userdef_default_theme.c
+++ b/release/datafiles/userdef/userdef_default_theme.c
@@ -1101,6 +1101,32 @@ const bTheme U_theme_default = {
       .active = RGBA(0x000000ff),
     },
   },
+  .collection_color = {
+    {
+      .color = RGBA(0xe4312bff),
+    },
+    {
+      .color = RGBA(0xef7e42ff),
+    },
+    {
+      .color = RGBA(0xe4dd52ff),
+    },
+    {
+      .color = RGBA(0x9ac546ff),
+    },
+    {
+      .color = RGBA(0x46bcc2ff),
+    },
+    {
+      .color = RGBA(0x8b65dcff),
+    },
+    {
+      .color = RGBA(0x999999ff),
+    },
+    {
+      .color = RGBA(0x06d4432ff),
+    },
+  },
 };
 
 /* clang-format on */
diff --git a/release/scripts/startup/bl_ui/space_outliner.py b/release/scripts/startup/bl_ui/space_outliner.py
index 5a54d4ca2d8..0c8c4df0c51 100644
--- a/release/scripts/startup/bl_ui/space_outliner.py
+++ b/release/scripts/startup/bl_ui/space_outliner.py
@@ -239,6 +239,10 @@ class OUTLINER_MT_collection(Menu):
         if space.display_mode == 'VIEW_LAYER':
             layout.separator()
             layout.menu("OUTLINER_MT_collection_view_layer", icon='RENDERLAYERS')
+            layout.separator()
+
+            row = layout.row(align=True)
+            row.operator_enum("outliner.collection_color_tag_set", "color", icon_only=True)
 
         layout.separator()
 
diff --git a/release/scripts/startup/bl_ui/space_userpref.py b/release/scripts/startup/bl_ui/space_userpref.py
index 9548de20752..61b2489bb4a 100644
--- a/release/scripts/startup/bl_ui/space_userpref.py
+++ b/release/scripts/startup/bl_ui/space_userpref.py
@@ -1019,6 +1019,24 @@ class USERPREF_PT_theme_bone_color_sets(ThemePanel, CenterAlignMixIn, Panel):
             flow.prop(ui, "active")
             flow.prop(ui, "show_colored_constraints")
 
+class USERPREF_PT_theme_collection_colors(ThemePanel, CenterAlignMixIn, Panel):
+    bl_label = "Collection Colors"
+    bl_options = {'DEFAULT_CLOSED'}
+
+    def draw_header(self, _context):
+        layout = self.layout
+
+        layout.label(icon='GROUP')
+
+    def draw_centered(self, context, layout):
+        theme = context.preferences.themes[0]
+
+        layout.use_property_split = True
+
+        flow = layout.grid_flow(row_major=False, columns=0, even_columns=True, even_rows=False, align=False)
+        for i, ui in enumerate(theme.collection_color, 1):
+            flow.prop(ui, "color", text=iface_(f"Color {i:d}"), translate=False)
+
 
 # Base class for dynamically defined theme-space panels.
 # This is not registered.
@@ -2254,6 +2272,7 @@ classes = (
     USERPREF_PT_theme_interface_icons,
     USERPREF_PT_theme_text_style,
     USERPREF_PT_theme_bone_color_sets,
+    USERPREF_PT_theme_collection_colors,
 
     USERPREF_PT_file_paths_data,
     USERPREF_PT_file_paths_render,
diff --git a/source/blender/blenloader/intern/versioning_userdef.c b/source/blender/blenloader/intern/versioning_userdef.c
index 0b116804481..475f618b1f4 100644
--- a/source/blender/blenloader/intern/versioning_userdef.c
+++ b/source/blender/blenloader/intern/versioning_userdef.c
@@ -217,6 +217,15 @@ static void do_versions_theme(const UserDef *userdef, bTheme *btheme)
     btheme->tui.transparent_checker_size = U_theme_default.tui.transparent_checker_size;
   }
 
+  FROM_DEFAULT_V4_UCHAR(collection_color[0].color);
+  FROM_DEFAULT_V4_UCHAR(collection_color[1].color);
+  FROM_DEFAULT_V4_UCHAR(collection_color[2].color);
+  FROM_DEFAULT_V4_UCHAR(collection_color[3].color);
+  FROM_DEFAULT_V4_UCHAR(collection_color[4].color);
+  FROM_DEFAULT_V4_UCHAR(collection_color[5].color);
+  FROM_DEFAULT_V4_UCHAR(collection_color[6].color);
+  FROM_DEFAULT_V4_UCHAR(collection_color[7].color);
+
   /**
    * Versioning code until next subversion bump goes here.
    *
diff --git a/source/blender/editors/animation/keyframing.c b/source/blender/editors/animation/keyframing.c
index 66d4882cf9d..e671a5b18f7 100644
--- a/source/blender/editors/animation/keyframing.c
+++ b/source/blender/editors/animation/keyframing.c
@@ -1971,7 +1971,7 @@ static int insert_key_menu_invoke(bContext *C, wmOperator *op, const wmEvent *UN
     /* call the menu, which will call this operator again, hence the canceled */
     pup = UI_popup_menu_begin(C, WM_operatortype_name(op->type, op->ptr), ICON_NONE);
     layout = UI_popup_menu_layout(pup);
-    uiItemsEnumO(layout, "ANIM_OT_keyframe_insert_menu", "type");
+    uiItemsEnumO(layout, "ANIM_OT_keyframe_insert_menu", "type", false);
     UI_popup_menu_end(C, pup);
 
     return OPERATOR_INTERFACE;
diff --git a/source/blender/editors/animation/keyingsets.c b/source/blender/editors/animation/keyingsets.c
index 876740b889a..558a7be1df8 100644
--- a/source/blender/editors/animation/keyingsets.c
+++ b/source/blender/editors/animation/keyingsets.c
@@ -479,7 +479,7 @@ static int keyingset_active_menu_invoke(bContext *C, wmOperator *op, const wmEve
   /* call the menu, which will call this operator again, hence the canceled */
   pup = UI_popup_menu_begin(C, op->type->name, ICON_NONE);
   layout = UI_popup_menu_layout(pup);
-  uiItemsEnumO(layout, "ANIM_OT_keying_set_active_set", "type");
+  uiItemsEnumO(layout, "ANIM_OT_keying_set_active_set", "type", false);
   UI_popup_menu_end(C, pup);
 
   return OPERATOR_INTERFACE;
diff --git a/source/blender/editors/curve/editcurve.c b/source/blender/editors/curve/editcurve.c
index d113e0693a4..c1668080d56 100644
--- a/source/blender/editors/curve/editcurve.c
+++ b/source/blender/editors/curve/editcurve.c
@@ -5922,7 +5922,7 @@ static int toggle_cyclic_invoke(bContext *C, wmOperator *op, const wmEvent *UNUS
         if (nu->type == CU_NURBS) {
           pup = UI_popup_menu_begin(C, IFACE_("Direction"), ICON_NONE);
           layout = UI_popup_menu_layout(pup);
-          uiItemsEnumO(layout, op->type->idname, "direction");
+          uiItemsEnumO(layout, op->type->idname, "direction", false);
           UI_popup_menu_end(C, pup);
           return OPERATOR_INTERFACE;
         }
diff --git a/source/blender/editors/gpencil/gpencil_data.c b/source/blender/editors/gpencil/gpencil_data.c
index 348fb614977..ed78f9e81f6 100644
--- a/source/blender/editors/gpencil/gpencil_data.c
+++ b/source/blender/editors/gpencil/gpencil_data.c
@@ -1403,7 +1403,7 @@ static int gpencil_layer_change_invoke(bContext *C, wmOperator *op, const wmEven
   /* call the menu, which will call this operator again, hence the canceled */
   pup = UI_popup_menu_begin(C, op->type->name, ICON_NONE);
   layout = UI_popup_menu_layout(pup);
-  uiItemsEnumO(layout, "GPENCIL_OT_layer_change", "layer");
+  uiItemsEnumO(layout, "GPENCIL_OT_layer_change", "layer", false);
   UI_popup_menu_end(C, pup);
 
   return OPERATOR_INTERFACE;
diff --git a/source/blender/editors/include/UI_icons.h b/source/blender/editors/include/UI_icons.h
index 452a1fca111..e976aac27a2 100644
--- a/source/blender/editors/include/UI_icons.h
+++ b/source/blender/editors/include/UI_icons.h
@@ -320,7 +320,7 @@ DEF_ICON_OBJECT(OUTLINER_OB_GROUP_INSTANCE)
 DEF_ICON_OBJECT(OUTLINER_OB_GREASEPENCIL)
 DEF_ICON_OBJECT(OUTLINER_OB_LIGHTPROBE)
 DEF_ICON_OBJECT(OUTLINER_OB_IMAGE)
-DEF_ICON_BLANK(321)
+DEF_ICON(OUTLINER_COLLECTION)
 DEF_ICON(RESTRICT_COLOR_OFF)
 DEF_ICON(RESTRICT_COLOR_ON)
 DEF_ICON(HIDE_ON)
@@ -980,6 +980,15 @@ DEF_ICON_VECTOR(COLORSET_18_VEC)
 DEF_ICON_VECTOR(COLORSET_19_VEC)
 DEF_ICON_VECTOR(COLORSET_20_VEC)
 
+DEF_ICON_VECTOR(COLLECTION_COLOR_01)
+DEF_ICON_VECTOR(COLLECTION_COLOR_02)
+DEF_ICON_VECTOR(COLLECTION_COLOR_03)
+DEF_ICON_VECTOR(COLLECTION_COLOR_04)
+DEF_ICON_VECTOR(COLLECTION_COLOR_05)
+DEF_ICON_VECTOR(COLLECTION_COLOR_06)
+DEF_ICON_VECTOR(COLLECTION_COLOR_07)
+DEF_ICON_VECTOR(COLLECTION_COLOR_08)
+
 /* Events  */
 DEF_ICON_COLOR(EVENT_A)
 DEF_ICON_COLOR(EVENT_B)
diff --git a/source/blender/editors/include/UI_interface.h b/source/blender/editors/include/UI_interface.h
index 5d936cdfaa3..f942ca8bafa 100644
--- a/source/blender/editors/include/UI_interface.h
+++ b/source/blender/editors/include/UI_interface.h
@@ -2208,7 +2208,10 @@ void uiItemEnumO_string(uiLayout *layout,
                         const char *opname,
                         const char *propname,
                         const char *value);
-void uiItemsEnumO(uiLayout *layout, const char *opname, const char *propname);
+void uiItemsEnumO(uiLayout *layout,
+                  const char *opname,
+                  const char *propname,
+                  const bool icon_only);
 void uiItemBooleanO(uiLayout *layout,
                     const char *name,
                     int icon,
diff --git a/source/blender/editors/include/UI_interface_icons.h b/source/blender/editors/include/UI_interface_icons.h
index 7b59d45b203..0e0891cb526 100644
--- a/source/blender/editors/include/UI_interface_icons.h
+++ b/source/blender/editors/include/UI_interface_icons.h
@@ -32,6 +32,7 @@ struct PointerRNA;
 struct PreviewImage;
 struct Scene;
 struct bContext;
+struct Collection;
 
 enum eIconSizes;
 
@@ -106,6 +107,7 @@ struct PreviewImage *UI_icon_to_preview(int icon_id);
 int UI_rnaptr_icon_get(struct bContext *C, struct PointerRNA *ptr, int rnaicon, const bool big);
 int UI_idcode_icon_get(const int idcode);
 int UI_library_icon_get(const struct ID *id);
+int UI_collection_color_icon_get(const struct Collection *collection);
 
 #ifdef __cplusplus
 }
diff --git a/source/blender/editors/interface/interface.c b/source/blender/editors/interface/interface.c
index e04531bb1dd..4a68d7f861c 100644
--- a/source/blender/editors/interface/interface.c
+++ b/source/blender/editors/interface/interface.c
@@ -383,13 +383,27 @@ static void ui_block_bounds_calc_text(uiBlock *block, float offset)
       }
     }
 
+    /* Keep aligned buttons in the same column. */
+    if (bt->alignnr && bt->next) {
+      int width = 0;
+      for (col_bt = bt; col_bt->rect.xmin < col_bt->next->rect.xmin; col_bt = col_bt->next) {
+        width += BLI_rctf_size_x(&col_bt->rect);
+      }
+      if (width > i) {
+        i = width;
+      }
+      bt = col_bt;
+    }
+
     if (bt->next && bt->rect.xmin < bt->next->rect.xmin) {
       /* End of this column, and it's not the last one. */
       for (col_bt = init_col_bt; col_bt->prev != bt; col_bt = col_bt->next) {
-        col_bt->rect.xmin = x1addval;
-        col_bt->rect.xmax = x1addval + i + block->bounds;
+        if (!col_bt->alignnr) {
+          col_bt->rect.xmin = x1addval;
+          col_bt->rect.xmax = x1addval + i + block->bounds;
 
-        ui_but_update(col_bt); /* clips text again */
+          ui_but_update(col_bt); /* clips text again */
+        }
       }
 
       /* And we prepare next column. */
@@ -401,8 +415,10 @@ static void ui_block_bounds_calc_text(uiBlock *block, float offset)
 
   /* Last column. */
   for (col_bt = init_col_bt; col_bt; col_bt = col_bt->next) {
-    col_bt->rect.xmin = x1addval;
-    col_bt->rect.xmax = max_ff(x1addval + i + block->bounds, offset + block->minbounds);
+    if (!col_bt->alignnr) {
+      col_bt->rect.xmin = x1addval;
+      col_bt->rect.xmax = max_ff(x1addval + i + block->bounds, offset + block->minbounds);
+    }
 
     ui_but_update(col_bt); /* clips text again */
   }
diff --git a/source/blender/editors/interface/interface_icons.c b/source/blender/editors/interface/interface_icons.c
index edf66d82cbc..a7a59fd8513 100644
--- a/source/blender/editors/interface/interface_icons.c
+++ b/source/blender/editors/interface/interface_icons.c
@@ -40,6 +40,7 @@
 #include "BLI_utildefines.h"
 
 #include "DNA_brush_types.h"
+#include "DNA_collection_types.h"
 #include "DNA_curve_types.h"
 #include "DNA_dynamicpaint_types.h"
 #include "DNA_gpencil_types.h"
@@ -460,6 +461,33 @@ DEF_ICON_VECTOR_COLORSET_DRAW_NTH(20, 19)
 
 #  undef DEF_ICON_VECTOR_COLORSET_DRAW_NTH
 
+static void vicon_collection_color_draw(
+    short color, int x, int y, int UNUSED(w), int UNUSED(), float UNUSED(alpha))
+{
+  bTheme *btheme = UI_GetTheme();
+  const ThemeCollectionColor *collection_color = &btheme->collection_color[color - 1];
+
+  UI_icon_draw_ex(
+      x, y, ICON_OUTLINER_COLLECTION, U.inv_dpi_fac, 1.0f, 0.0f, collection_color->color, true);
+}
+
+#  define DEF_ICON_COLLECTION_COLOR_DRAW(index, color) \
+    static void vicon_collection_color_draw_##index(int x, int y, int w, int h, float alpha) \
+    { \
+      vicon_collection_color_draw(color, x, y, w, h, alpha); \
+    }
+
+DEF_ICON_COLLECTION_COLOR_DRAW(01, COLLECTION_COLOR_01);
+DEF_ICON_COLLECTION_COLOR_DRAW(02, COLLECTION_COLOR_02);
+DEF_ICON_COLLECTION_COLOR_DRAW(03, COLLECTION_COLOR_03);
+DEF_ICON_COLLECTION_COLOR_DRAW(04, COLLECTION_COLOR_04);
+DEF_ICON_COLLECTION_COLOR_DRAW(05, COLLECTION_COLOR_05);
+DEF_ICON_COLLECTION_COLOR_DRAW(06, COLLECTION_COLOR_06);
+DEF_ICON_COLLECTION_COLOR_DRAW(07, COLLECTION_COLOR_07);
+DEF_ICON_COLLECTION_COLOR_DRAW(08, COLLECTION_COLOR_08);
+
+#  undef DEF_ICON_COLLECTION_COLOR_DRAW
+
 /* Dynamically render icon instead of rendering a plain color to a texture/buffer
  * This is not strictly a "vicon", as it needs access to icon->obj to get the color info,
  * but it works in a very similar way.
@@ -985,6 +1013,15 @@ static void init_internal_icons(void)
   def_internal_vicon(ICON_COLORSET_18_VEC, vicon_colorset_draw_18);
   def_internal_vicon(ICON_COLORSET_19_VEC, vicon_colorset_draw_19);
   def_internal_vicon(ICON_COLORSET_20_VEC, vicon_colorset_draw_20);
+
+  def_internal_vicon(ICON_COLLECTION_COLOR_01, vicon_collection_color_draw_01);
+  def_internal_vicon(ICON_COLLECTION_COLOR_02, vicon_collection_color_draw_02);
+  def_internal_vicon(ICON_COLLECTION_COLOR_03, vicon_collection_color_draw_03);
+  def_internal_vicon(ICON_COLLECTION_COLOR_04, vicon_collection_color_draw_04);
+  def_internal_vicon(ICON_COLLECTION_COLOR_05, vicon_collection_color_draw_05);
+  def_internal_vicon(ICON_COLLECTION_COLOR_06, vicon_collection_color_draw_06);
+  def_internal_vicon(ICON_COLLECTION_COLOR_07, vicon_collection_color_draw_07);
+  def_internal_vicon(ICON_COLLECTION_COLOR_08, vicon_collection_color_draw_08);
 }
 #  endif /* WITH_HEADLESS */
 
@@ -2148,6 +2185,9 @@ int ui_id_icon_get(const bContext *C, ID *id, const bool big)
     case ID_SCR:
       iconid = ui_id_screen_get_icon(C, id);
       break;
+    case ID_GR:
+      iconid = UI_collection_color_icon_get((Collection *)id);
+      break;
     default:
       break;
   }
@@ -2309,6 +2349,17 @@ int UI_idcode_icon_get(const int idcode)
   }
 }
 
+int UI_collection_color_icon_get(const Collection *collection)
+{
+  int icon = ICON_OUTLINER_COLLECTION;
+
+  if (collection->color != COLLECTION_COLOR_NONE) {
+    icon = ICON_COLLECTION_COLOR_01 + (collection->color - 1);
+  }
+
+  return icon;
+}
+
 /* draws icon with dpi scale factor */
 void UI_icon_draw(float x, float y, int icon_id)
 {
diff --git a/source/blender/editors/interface/interface_layout.c b/source/blender/editors/interface/interface_layout.c
index ad76466b67c..f19596c7ba7 100644
--- a/source/blender/editors/interface/interface_layout.c
+++ b/source/blender/editors/interface/interface_layout.c
@@ -1208,6 +1208,10 @@ static uiBut *uiItemFullO_ptr_ex(uiLayout *layout,
     but->flag |= UI_SELECT_DRAW;
   }
 
+  if (flag & UI_ITEM_R_ICON_ONLY) {
+    UI_but_drawflag_disable(but, UI_BUT_ICON_LEFT);
+  }
+
   if (layout->redalert) {
     UI_but_flag_enable(but, UI_BUT_REDALERT);
   }
@@ -1428,6 +1432,13 @@ void uiItemsFullEnumO_items(uiLayout *layout,
   if (radial) {
     target = uiLayoutRadial(layout);
   }
+  else if (layout->item.type == ITEM_LAYOUT_ROW && flag & UI_ITEM_R_ICON_ONLY) {
+    target = layout;
+
+    /* Add a blank button to the beginning of the row. */
+    uiDefIconBut(
+        block, UI_BTYPE_LABEL, 0, ICON_BLANK1, 0, 0, UI_UNIT_X, UI_UNIT_Y, NULL, 0, 0, 0, 0, NULL);
+  }
   else {
     split = uiLayoutSplit(layout, 0.0f, false);
     target = uiLayoutColumn(split, layout->align);
@@ -1475,7 +1486,14 @@ void uiItemsFullEnumO_items(uiLayout *layout,
       }
       RNA_property_enum_set(&tptr, prop, item->value);
 
-      uiItemFullO_ptr(target, ot, item->name, item->icon, tptr.data, context, flag, NULL);
+      uiItemFullO_ptr(target,
+                      ot,
+                      (flag & UI_ITEM_R_ICON_ONLY) ? NULL : item->name,
+                      item->icon,
+                      tptr.data,
+                      context,
+                      flag,
+                      NULL);
 
       ui_but_tip_from_enum_item(block->buttons.last, item);
     }
@@ -1599,9 +1617,14 @@ void uiItemsFullEnumO(uiLayout *layout,
   }
 }
 
-void uiItemsEnumO(uiLayout *layout, const char *opname, const char *propname)
+void uiItemsEnumO(uiLayout *layout, const char *opname, const char *propname, const bool icon_only)
 {
-  uiItemsFullEnumO(layout, opname, propname, NULL, layout->root->opcontext, 0);
+  uiItemsFullEnumO(layout,
+                   opname,
+                   propname,
+                   NULL,
+                   layout->root->opcontext,
+                   icon_only ? UI_ITEM_R_ICON_ONLY : 0);
 }
 
 /* for use in cases where we have */
@@ -3372,7 +3395,7 @@ static void menu_item_enum_opname_menu(bContext *UNUSED(C), uiLayout *layout, vo
   MenuItemLevel *lvl = (MenuItemLevel *)(((uiBut *)arg)->func_argN);
 
   uiLayoutSetOperatorContext(layout, lvl->opcontext);
-  uiItemsEnumO(layout, lvl->opname, lvl->propname);
+  uiItemsEnumO(layout, lvl->opname, lvl->propname, false);
 
   layout->root->block->flag |= UI_BLOCK_IS_FLIP;
 
@@ -3718,18 +3741,18 @@ static void ui_litem_estimate_column(uiLayout *litem, bool is_box)
   }
 }
 
-static void ui_litem_layout_column(uiLayout *litem, bool is_box)
+static void ui_litem_layout_column(uiLayout *litem, bool is_box, bool is_menu)
 {
-  int itemh, x, y;
+  int itemw, itemh, x, y;
 
   x = litem->x;
   y = litem->y;
 
   LISTBASE_FOREACH (uiItem *, item, &litem->items) {
-    ui_item_size(item, NULL, &itemh);
+    ui_item_size(item, &itemw, &itemh);
 
     y -= itemh;
-    ui_item_position(item, x, y, litem->w, itemh);
+    ui_item_position(item, x, y, is_menu ? itemw : litem->w, itemh);
 
     if (item->next && (!is_box || item != litem->items.first)) {
       y -= litem->space;
@@ -3890,8 +3913,11 @@ static void ui_litem_layout_root(uiLayout *litem)
   else if (litem->root->type == UI_LAYOUT_PIEMENU) {
     ui_litem_layout_root_radial(litem);
   }
+  else if (litem->root->type == UI_LAYOUT_MENU) {
+    ui_litem_layout_column(litem, false, true);
+  }
   else {
-    ui_litem_layout_column(litem, false);
+    ui_litem_layout_column(litem, false, false);
   }
 }
 
@@ -3935,7 +3961,7 @@ static void ui_litem_layout_box(uiLayout *litem)
     litem->h -= 2 * boxspace;
   }
 
-  ui_litem_layout_column(litem, true);
+  ui_litem_layout_column(litem, true, false);
 
   litem->x -= boxspace;
   litem->y -= boxspace;
@@ -5196,7 +5222,7 @@ static void ui_item_layout(uiItem *item)
 
     switch (litem->item.type) {
       case ITEM_LAYOUT_COLUMN:
-        ui_litem_layout_column(litem, false);
+        ui_litem_layout_column(litem, false, false);
         break;
       case ITEM_LAYOUT_COLUMN_FLOW:
         ui_litem_layout_column_flow(litem);
diff --git a/source/blender/editors/interface/interface_region_menu_pie.c b/source/blender/editors/interface/interface_region_menu_pie.c
index 1371c7524ae..5afef38ae0d 100644
--- a/source/blender/editors/interface/interface_region_menu_pie.c
+++ b/source/blender/editors/interface/interface_region_menu_pie.c
@@ -261,7 +261,7 @@ int UI_pie_menu_invoke_from_operator_enum(struct bContext *C,
   layout = UI_pie_menu_layout(pie);
 
   layout = uiLayoutRadial(layout);
-  uiItemsEnumO(layout, opname, propname);
+  uiItemsEnumO(layout, opname, propname, false);
 
   UI_pie_menu_end(C, pie);
 
diff --git a/source/blender/editors/interface/interface_widgets.c b/source/blender/editors/interface/interface_widgets.c
index c1801290152..fa2f2b0d1b9 100644
--- a/source/blender/editors/interface/interface_widgets.c
+++ b/source/blender/editors/interface/interface_widgets.c
@@ -2375,7 +2375,7 @@ static void widget_draw_text_icon(const uiFontStyle *fstyle,
         rect->xmin += 0.3f * U.widget_unit;
       }
     }
-    else if (ui_block_is_menu(but->block)) {
+    else if (ui_block_is_menu(but->block) && but->alignnr == 0) {
       rect->xmin += 0.2f * U.widget_unit;
     }
 
diff --git a/source/blender/editors/object/object_collection.c b/source/blender/editors/object/object_collection.c
index 24f6d8c79f9..5f14cdcd299 100644
--- a/source/blender/editors/object/object_collection.c
+++ b/source/blender/editors/object/object_collection.c
@@ -50,6 +50,8 @@
 #include "RNA_define.h"
 #include "RNA_enum_types.h"
 
+#include "UI_interface_icons.h"
+
 #include "object_intern.h"
 
 /********************* 3d view operators ***********************/
@@ -94,7 +96,7 @@ static const EnumPropertyItem *collection_object_active_itemf(bContext *C,
     collection = NULL;
     while ((collection = BKE_collection_object_find(bmain, scene, collection, ob))) {
       item_tmp.identifier = item_tmp.name = collection->id.name + 2;
-      /* item_tmp.icon = ICON_ARMATURE_DATA; */
+      item_tmp.icon = UI_collection_color_icon_get(collection);
       item_tmp.value = i;
       RNA_enum_item_add(&item, &totitem, &item_tmp);
       i++;
diff --git a/source/blender/editors/object/object_edit.c b/source/blender/editors/object/object_edit.c
index 04113f70e52..c911d62f392 100644
--- a/source/blender/editors/object/object_edit.c
+++ b/source/blender/editors/object/object_edit.c
@@ -100,6 +100,8 @@
 #include "RNA_define.h"
 #include "RNA_enum_types.h"
 
+#include "UI_interface_icons.h"
+
 #include "CLG_log.h"
 
 /* for menu/popup icons etc etc*/
@@ -1761,7 +1763,7 @@ static void move_to_collection_menus_free(MoveToCollectionData **menu)
   *menu = NULL;
 }
 
-static void move_to_collection_menu_create(bContext *UNUSED(C), uiLayout *layout, void *menu_v)
+static void move_to_collection_menu_create(bContext *C, uiLayout *layout, void *menu_v)
 {
   MoveToCollectionData *menu = menu_v;
   const char *name = BKE_collection_ui_name_get(menu->collection);
@@ -1777,7 +1779,11 @@ static void move_to_collection_menu_create(bContext *UNUSED(C), uiLayout *layout
 
   uiItemS(layout);
 
-  uiItemIntO(layout, name, ICON_SCENE_DATA, menu->ot->idname, "collection_index", menu->index);
+  Scene *scene = CTX_data_scene(C);
+  const int icon = (menu->collection == scene->master_collection) ?
+                       ICON_SCENE_DATA :
+                       UI_collection_color_icon_get(menu->collection);
+  uiItemIntO(layout, name, icon, menu->ot->idname, "collection_index", menu->index);
 
   for (MoveToCollectionData *submenu = menu->submenus.first; submenu != NULL;
        submenu = submenu->next) {
@@ -1787,17 +1793,18 @@ static void move_to_collection_menu_create(bContext *UNUSED(C), uiLayout *layout
 
 static void move_to_collection_menus_items(uiLayout *layout, MoveToCollectionData *menu)
 {
+  const int icon = UI_collection_color_icon_get(menu->collection);
+
   if (BLI_listbase_is_empty(&menu->submenus)) {
     uiItemIntO(layout,
                menu->collection->id.name + 2,
-               ICON_NONE,
+               icon,
                menu->ot->idname,
                "collection_index",
                menu->index);
   }
   else {
-    uiItemMenuF(
-        layout, menu->collection->id.name + 2, ICON_NONE, move_to_collection_menu_create, menu);
+    uiItemMenuF(layout, menu->collection->id.name + 2, icon, move_to_collection_menu_create, menu);
   }
 }
 
diff --git a/source/blender/editors/space_info/info_ops.c b/source/blender/editors/space_info/info_ops.c
index 30f36509b41..dda4d8a6c78 100644
--- a/source/blender/editors/space_info/info_ops.c
+++ b/source/blender/editors/space_info/info_ops.c
@@ -256,7 +256,7 @@ static int unpack_all_invoke(bContext *C, wmOperator *op, const wmEvent *UNUSED(
   layout = UI_popup_menu_layout(pup);
 
   uiLayoutSetOperatorContext(layout, WM_OP_EXEC_DEFAULT);
-  uiItemsEnumO(layout, "FILE_OT_unpack_all", "method");
+  uiItemsEnumO(layout, "FILE_OT_unpack_all", "method", false);
 
   UI_popup_menu_end(C, pup);
 
diff --git a/source/blender/editors/space_outliner/outliner_collections.c b/source/blender/editors/space_outliner/outliner_collections.c
index efb91528e14..a76ee2972cc 100644
--- a/source/blender/editors/space_outliner/outliner_collections.c
+++ b/source/blender/editors/space_outliner/outliner_collections.c
@@ -1529,3 +1529,66 @@ void OUTLINER_OT_unhide_all(wmOperatorType *ot)
 }
 
 /** \} */
+
+/* -------------------------------------------------------------------- */
+/** \name Collection Color Tags
+ * \{ */
+
+static int outliner_color_tag_set_exec(bContext *C, wmOperator *op)
+{
+  Scene *scene = CTX_data_scene(C);
+  SpaceOutliner *space_outliner = CTX_wm_space_outliner(C);
+  const short color_tag = RNA_enum_get(op->ptr, "color");
+
+  struct IDsSelectedData selected = {
+      .selected_array = {NULL, NULL},
+  };
+
+  outliner_tree_traverse(space_outliner,
+                         &space_outliner->tree,
+                         0,
+                         TSE_SELECTED,
+                         outliner_find_selected_collections,
+                         &selected);
+
+  LISTBASE_FOREACH (LinkData *, link, &selected.selected_array) {
+    TreeElement *te_selected = (TreeElement *)link->data;
+
+    Collection *collection = outliner_collection_from_tree_element(te_selected);
+    if (collection == scene->master_collection) {
+      continue;
+    }
+    if (ID_IS_LINKED(collection)) {
+      BKE_report(op->reports, RPT_WARNING, "Can't add a color tag to a linked collection");
+      continue;
+    }
+
+    collection->color = color_tag;
+  };
+
+  BLI_freelistN(&selected.selected_array);
+
+  WM_event_add_notifier(C, NC_SCENE | ND_LAYER_CONTENT, NULL);
+
+  return OPERATOR_FINISHED;
+}
+
+void OUTLINER_OT_collection_color_tag_set(wmOperatorType *ot)
+{
+  /* identifiers */
+  ot->name = "Set Color Tag";
+  ot->idname = "OUTLINER_OT_collection_color_tag_set";
+  ot->description = "Set a color tag for the selected collections";
+
+  /* api callbacks */
+  ot->exec = outliner_color_tag_set_exec;
+  ot->poll = ED_outliner_collections_editor_poll;
+
+  /* flags */
+  ot->flag = OPTYPE_REGISTER | OPTYPE_UNDO;
+
+  RNA_def_enum(
+      ot->srna, "color", rna_enum_collection_color_items, COLLECTION_COLOR_NONE, "Color Tag", "");
+}
+
+/** \} */
diff --git a/source/blender/editors/space_outliner/outliner_draw.c b/source/blender/editors/space_outliner/outliner_draw.c
index 1705b9dd606..5cc42cbadbb 100644
--- a/source/blender/editors/space_outliner/outliner_draw.c
+++ b/source/blender/editors/space_outliner/outliner_draw.c
@@ -848,8 +848,8 @@ typedef struct RestrictProperties {
   PropertyRNA *object_hide_viewport, *object_hide_select, *object_hide_render;
   PropertyRNA *base_hide_viewport;
   PropertyRNA *collection_hide_viewport, *collection_hide_select, *collection_hide_render;
-  PropertyRNA *layer_collection_holdout, *layer_collection_indirect_only,
-      *layer_collection_hide_viewport;
+  PropertyRNA *layer_collection_exclude, *layer_collection_holdout,
+      *layer_collection_indirect_only, *layer_collection_hide_viewport;
   PropertyRNA *modifier_show_viewport, *modifier_show_render;
   PropertyRNA *constraint_enable;
   PropertyRNA *bone_hide_viewport;
@@ -865,6 +865,7 @@ typedef struct RestrictPropertiesActive {
   bool collection_hide_viewport;
   bool collection_hide_select;
   bool collection_hide_render;
+  bool layer_collection_exclude;
   bool layer_collection_holdout;
   bool layer_collection_indirect_only;
   bool layer_collection_hide_viewport;
@@ -954,8 +955,7 @@ static bool outliner_restrict_properties_collection_set(Scene *scene,
                                                                                NULL;
   Collection *collection = outliner_collection_from_tree_element(te);
 
-  if ((collection->flag & COLLECTION_IS_MASTER) ||
-      (layer_collection && ((layer_collection->flag & LAYER_COLLECTION_EXCLUDE) != 0))) {
+  if (collection->flag & COLLECTION_IS_MASTER) {
     return false;
   }
 
@@ -995,6 +995,8 @@ static void outliner_draw_restrictbuts(uiBlock *block,
                                                                    "hide_viewport");
     props.collection_hide_select = RNA_struct_type_find_property(&RNA_Collection, "hide_select");
     props.collection_hide_render = RNA_struct_type_find_property(&RNA_Collection, "hide_render");
+    props.layer_collection_exclude = RNA_struct_type_find_property(&RNA_LayerCollection,
+                                                                   "exclude");
     props.layer_collection_holdout = RNA_struct_type_find_property(&RNA_LayerCollection,
                                                                    "holdout");
     props.layer_collection_indirect_only = RNA_struct_type_find_property(&RNA_LayerCollection,
@@ -1012,6 +1014,7 @@ static void outliner_draw_restrictbuts(uiBlock *block,
   }
 
   struct {
+    int enable;
     int select;
     int hide;
     int viewport;
@@ -1042,6 +1045,11 @@ static void outliner_draw_restrictbuts(uiBlock *block,
   if (space_outliner->show_restrict_flags & SO_RESTRICT_SELECT) {
     restrict_offsets.select = (++restrict_column_offset) * UI_UNIT_X + V2D_SCROLL_WIDTH;
   }
+  if (space_outliner->outlinevis == SO_VIEW_LAYER &&
+      space_outliner->show_restrict_flags & SO_RESTRICT_ENABLE) {
+    restrict_offsets.enable = (++restrict_column_offset) * UI_UNIT_X + V2D_SCROLL_WIDTH;
+  }
+
   BLI_assert((restrict_column_offset * UI_UNIT_X + V2D_SCROLL_WIDTH) ==
              outliner_restrict_columns_width(space_outliner));
 
@@ -1430,6 +1438,26 @@ static void outliner_draw_restrictbuts(uiBlock *block,
           Collection *collection = outliner_collection_from_tree_element(te);
 
           if (layer_collection != NULL) {
+            if (space_outliner->show_restrict_flags & SO_RESTRICT_ENABLE) {
+              bt = uiDefIconButR_prop(block,
+                                      UI_BTYPE_ICON_TOGGLE,
+                                      0,
+                                      0,
+                                      (int)(region->v2d.cur.xmax) - restrict_offsets.enable,
+                                      te->ys,
+                                      UI_UNIT_X,
+                                      UI_UNIT_Y,
+                                      &layer_collection_ptr,
+                                      props.layer_collection_exclude,
+                                      -1,
+                                      0,
+                                      0,
+                                      0,
+                                      0,
+                                      NULL);
+              UI_but_flag_enable(bt, UI_BUT_DRAG_LOCK);
+            }
+
             if (space_outliner->show_restrict_flags & SO_RESTRICT_HIDE) {
               bt = uiDefIconButR_prop(block,
                                       UI_BTYPE_ICON_TOGGLE,
@@ -1823,7 +1851,6 @@ static void outliner_buttons(const bContext *C,
                              const float restrict_column_width,
                              TreeElement *te)
 {
-  SpaceOutliner *space_outliner = CTX_wm_space_outliner(C);
   uiBut *bt;
   TreeStoreElem *tselem;
   int spx, dx, len;
@@ -1849,10 +1876,6 @@ static void outliner_buttons(const bContext *C,
   }
 
   spx = te->xs + 1.8f * UI_UNIT_X;
-  if ((tselem->type == TSE_LAYER_COLLECTION) &&
-      (space_outliner->show_restrict_flags & SO_RESTRICT_ENABLE)) {
-    spx += UI_UNIT_X;
-  }
   dx = region->v2d.cur.xmax - (spx + restrict_column_width + 0.2f * UI_UNIT_X);
 
   bt = uiDefBut(block,
@@ -2347,7 +2370,7 @@ TreeElementIcon tree_element_get_icon(TreeStoreElem *tselem, TreeElement *te)
           data.drag_parent = (data.drag_id && te->parent) ? TREESTORE(te->parent)->id : NULL;
         }
 
-        data.icon = ICON_GROUP;
+        data.icon = ICON_OUTLINER_COLLECTION;
         break;
       }
       case TSE_GP_LAYER: {
@@ -2578,60 +2601,6 @@ TreeElementIcon tree_element_get_icon(TreeStoreElem *tselem, TreeElement *te)
   return data;
 }
 
-static void tselem_draw_layer_collection_enable_icon(
-    Scene *scene, uiBlock *block, int xmax, float x, float y, TreeElement *te, float alpha)
-{
-  /* Get RNA property (once for speed). */
-  static PropertyRNA *exclude_prop = NULL;
-  if (exclude_prop == NULL) {
-    exclude_prop = RNA_struct_type_find_property(&RNA_LayerCollection, "exclude");
-  }
-
-  if (x >= xmax) {
-    /* Placement of icons, copied from interface_widgets.c. */
-    float aspect = (0.8f * UI_UNIT_Y) / ICON_DEFAULT_HEIGHT;
-    x += 2.0f * aspect;
-    y += 2.0f * aspect;
-
-    /* restrict column clip... it has been coded by simply overdrawing,
-     * doesn't work for buttons */
-    uchar color[4];
-    int icon = RNA_property_ui_icon(exclude_prop);
-    if (UI_icon_get_theme_color(icon, color)) {
-      UI_icon_draw_ex(x, y, icon, U.inv_dpi_fac, alpha, 0.0f, color, true);
-    }
-    else {
-      UI_icon_draw_ex(x, y, icon, U.inv_dpi_fac, alpha, 0.0f, NULL, false);
-    }
-  }
-  else {
-    LayerCollection *layer_collection = te->directdata;
-    PointerRNA layer_collection_ptr;
-    RNA_pointer_create(&scene->id, &RNA_LayerCollection, layer_collection, &layer_collection_ptr);
-
-    char emboss = UI_block_emboss_get(block);
-    UI_block_emboss_set(block, UI_EMBOSS_NONE);
-    uiBut *bt = uiDefIconButR_prop(block,
-                                   UI_BTYPE_ICON_TOGGLE,
-                                   0,
-                                   0,
-                                   x,
-                                   y,
-                                   UI_UNIT_X,
-                                   UI_UNIT_Y,
-                                   &layer_collection_ptr,
-                                   exclude_prop,
-                                   -1,
-                                   0,
-                                   0,
-                                   0,
-                                   0,
-                                   NULL);
-    UI_but_flag_enable(bt, UI_BUT_DRAG_LOCK);
-    UI_block_emboss_set(block, emboss);
-  }
-}
-
 static void tselem_draw_icon(uiBlock *block,
                              int xmax,
                              float x,
@@ -2647,8 +2616,30 @@ static void tselem_draw_icon(uiBlock *block,
     return;
   }
 
+  if (outliner_is_collection_tree_element(te)) {
+    Collection *collection = outliner_collection_from_tree_element(te);
+
+    /* placement of icons, copied from interface_widgets.c */
+    float aspect = (0.8f * UI_UNIT_Y) / ICON_DEFAULT_HEIGHT;
+    x += 2.0f * aspect;
+    y += 2.0f * aspect;
+    if (collection->color != COLLECTION_COLOR_NONE) {
+      bTheme *btheme = UI_GetTheme();
+      UI_icon_draw_ex(x,
+                      y,
+                      data.icon,
+                      U.inv_dpi_fac,
+                      alpha,
+                      0.0f,
+                      btheme->collection_color[collection->color - 1].color,
+                      true);
+    }
+    else {
+      UI_icon_draw_ex(x, y, data.icon, U.inv_dpi_fac, alpha, 0.0f, NULL, true);
+    }
+  }
   /* Icon is covered by restrict buttons */
-  if (!is_clickable || x >= xmax) {
+  else if (!is_clickable || x >= xmax) {
     /* Reduce alpha to match icon buttons */
     alpha *= 0.8f;
 
@@ -3039,15 +3030,6 @@ static void outliner_draw_tree_element(bContext *C,
     else {
       active = tree_element_type_active(C, tvc, space_outliner, te, tselem, OL_SETSEL_NONE, false);
       /* active collection*/
-      icon_bgcolor[3] = 0.2f;
-    }
-
-    /* Checkbox to enable collections. */
-    if ((tselem->type == TSE_LAYER_COLLECTION) &&
-        (space_outliner->show_restrict_flags & SO_RESTRICT_ENABLE)) {
-      tselem_draw_layer_collection_enable_icon(
-          tvc->scene, block, xmax, (float)startx + offsx + UI_UNIT_X, (float)*starty, te, 0.8f);
-      offsx += UI_UNIT_X;
     }
 
     /* active circle */
@@ -3196,6 +3178,17 @@ static void outliner_draw_tree_element(bContext *C,
   }
 }
 
+static bool subtree_contains_object(ListBase *lb)
+{
+  LISTBASE_FOREACH (TreeElement *, te, lb) {
+    TreeStoreElem *tselem = TREESTORE(te);
+    if (tselem->type == 0 && te->idcode == ID_OB) {
+      return true;
+    }
+  }
+  return false;
+}
+
 static void outliner_draw_hierarchy_lines_recursive(uint pos,
                                                     SpaceOutliner *space_outliner,
                                                     ListBase *lb,
@@ -3204,100 +3197,50 @@ static void outliner_draw_hierarchy_lines_recursive(uint pos,
                                                     bool draw_grayed_out,
                                                     int *starty)
 {
-  TreeElement *te, *te_vertical_line_last = NULL, *te_vertical_line_last_dashed = NULL;
-  int y1, y2, y1_dashed, y2_dashed;
+  bTheme *btheme = UI_GetTheme();
+  int y = *starty;
+  short color = 0;
 
-  if (BLI_listbase_is_empty(lb)) {
-    return;
-  }
+  /* Small vertical padding */
+  const short line_padding = UI_UNIT_Y / 4.0f;
 
-  struct {
-    int steps_num;
-    int step_len;
-    int gap_len;
-  } dash = {
-      .steps_num = 4,
-  };
-
-  dash.step_len = UI_UNIT_X / dash.steps_num;
-  dash.gap_len = dash.step_len / 2;
-
-  const uchar grayed_alpha = col[3] / 2;
-
-  /* For vertical lines between objects. */
-  y1 = y2 = y1_dashed = y2_dashed = *starty;
-  for (te = lb->first; te; te = te->next) {
-    bool draw_children_grayed_out = draw_grayed_out || (te->flag & TE_DRAGGING);
+  /* Draw vertical lines between collections */
+  bool draw_hierarchy_line;
+  LISTBASE_FOREACH (TreeElement *, te, lb) {
     TreeStoreElem *tselem = TREESTORE(te);
+    draw_hierarchy_line = false;
+    *starty -= UI_UNIT_Y;
 
-    if (draw_children_grayed_out) {
-      immUniformColor3ubvAlpha(col, grayed_alpha);
-    }
-    else {
-      immUniformColor4ubv(col);
-    }
+    /* Only draw hierarchy lines for open collections. */
+    if (TSELEM_OPEN(tselem, space_outliner) && !BLI_listbase_is_empty(&te->subtree)) {
+      if (tselem->type == TSE_LAYER_COLLECTION) {
+        draw_hierarchy_line = true;
 
-    if ((te->flag & TE_CHILD_NOT_IN_COLLECTION) == 0) {
-      /* Horizontal Line? */
-      if (tselem->type == 0 && (te->idcode == ID_OB || te->idcode == ID_SCE)) {
-        immRecti(pos, startx, *starty, startx + UI_UNIT_X, *starty - U.pixelsize);
+        Collection *collection = outliner_collection_from_tree_element(te);
+        color = collection->color;
 
-        /* Vertical Line? */
-        if (te->idcode == ID_OB) {
-          te_vertical_line_last = te;
-          y2 = *starty;
-        }
-        y1_dashed = *starty - UI_UNIT_Y;
+        y = *starty;
       }
-    }
-    else {
-      BLI_assert(te->idcode == ID_OB);
-      /* Horizontal line - dashed. */
-      int start = startx;
-      for (int i = 0; i < dash.steps_num; i++) {
-        immRecti(pos, start, *starty, start + dash.step_len - dash.gap_len, *starty - U.pixelsize);
-        start += dash.step_len;
+      else if (tselem->type == 0 && te->idcode == ID_OB) {
+        if (subtree_contains_object(&te->subtree)) {
+          draw_hierarchy_line = true;
+          y = *starty;
+        }
       }
 
-      te_vertical_line_last_dashed = te;
-      y2_dashed = *starty;
+      outliner_draw_hierarchy_lines_recursive(
+          pos, space_outliner, &te->subtree, startx + UI_UNIT_X, col, draw_grayed_out, starty);
     }
 
-    *starty -= UI_UNIT_Y;
-
-    if (TSELEM_OPEN(tselem, space_outliner)) {
-      outliner_draw_hierarchy_lines_recursive(pos,
-                                              space_outliner,
-                                              &te->subtree,
-                                              startx + UI_UNIT_X,
-                                              col,
-                                              draw_children_grayed_out,
-                                              starty);
-    }
-  }
-
-  if (draw_grayed_out) {
-    immUniformColor3ubvAlpha(col, grayed_alpha);
-  }
-  else {
-    immUniformColor4ubv(col);
-  }
-
-  /* Vertical line. */
-  te = te_vertical_line_last;
-  if ((te != NULL) && (te->parent || lb->first != lb->last)) {
-    immRecti(pos, startx, y1 + UI_UNIT_Y, startx + U.pixelsize, y2);
-  }
+    if (draw_hierarchy_line) {
+      if (color != COLLECTION_COLOR_NONE) {
+        immUniformColor4ubv(btheme->collection_color[color - 1].color);
+      }
+      else {
+        immUniformColor4ubv(col);
+      }
 
-  /* Children that are not in the collection are always in the end of the subtree.
-   * This way we can draw their own dashed vertical lines. */
-  te = te_vertical_line_last_dashed;
-  if ((te != NULL) && (te->parent || lb->first != lb->last)) {
-    const int steps_num = ((y1_dashed + UI_UNIT_Y) - y2_dashed) / dash.step_len;
-    int start = y1_dashed + UI_UNIT_Y;
-    for (int i = 0; i < steps_num; i++) {
-      immRecti(pos, startx, start, startx + U.pixelsize, start - dash.step_len + dash.gap_len);
-      start -= dash.step_len;
+      immRecti(pos, startx, y - line_padding, startx + (U.pixelsize * 1), *starty + line_padding);
     }
   }
 }
diff --git a/source/blender/editors/space_outliner/outliner_intern.h b/source/blender/editors/space_outliner/outliner_intern.h
index 33dbbb274c0..ad8f8a92b5f 100644
--- a/source/blender/editors/space_outliner/outliner_intern.h
+++ b/source/blender/editors/space_outliner/outliner_intern.h
@@ -482,6 +482,8 @@ void OUTLINER_OT_collection_disable_render(struct wmOperatorType *ot);
 void OUTLINER_OT_hide(struct wmOperatorType *ot);
 void OUTLINER_OT_unhide_all(struct wmOperatorType *ot);
 
+void OUTLINER_OT_collection_color_tag_set(struct wmOperatorType *ot);
+
 /* outliner_utils.c ---------------------------------------------- */
 
 void outliner_viewcontext_init(const struct bContext *C, TreeViewContext *tvc);
diff --git a/source/blender/editors/space_outliner/outliner_ops.c b/source/blender/editors/space_outliner/outliner_ops.c
index af7d97b6950..22541a0ab1f 100644
--- a/source/blender/editors/space_outliner/outliner_ops.c
+++ b/source/blender/editors/space_outliner/outliner_ops.c
@@ -117,6 +117,8 @@ void outliner_operatortypes(void)
   WM_operatortype_append(OUTLINER_OT_collection_show_inside);
   WM_operatortype_append(OUTLINER_OT_hide);
   WM_operatortype_append(OUTLINER_OT_unhide_all);
+
+  WM_operatortype_append(OUTLINER_OT_collection_color_tag_set);
 }
 
 void outliner_keymap(wmKeyConfig *keyconf)
diff --git a/source/blender/editors/space_outliner/outliner_tools.c b/source/blender/editors/space_outliner/outliner_tools.c
index 6532ff189b5..965e6d1177a 100644
--- a/source/blender/editors/space_outliner/outliner_tools.c
+++ b/source/blender/editors/space_outliner/outliner_tools.c
@@ -2588,7 +2588,7 @@ static int outliner_operator_menu(bContext *C, const char *opname)
 
   /* set this so the default execution context is the same as submenus */
   uiLayoutSetOperatorContext(layout, WM_OP_INVOKE_REGION_WIN);
-  uiItemsEnumO(layout, ot->idname, RNA_property_identifier(ot->prop));
+  uiItemsEnumO(layout, ot->idname, RNA_property_identifier(ot->prop), false);
 
   uiItemS(layout);
 
diff --git a/source/blender/editors/space_outliner/outliner_utils.c b/source/blender/editors/space_outliner/outliner_utils.c
index 1da44b5e51e..1e01a62875c 100644
--- a/source/blender/editors/space_outliner/outliner_utils.c
+++ b/source/blender/editors/space_outliner/outliner_utils.c
@@ -359,6 +359,9 @@ float outliner_restrict_columns_width(const SpaceOutliner *space_outliner)
       num_columns = 3;
       break;
     case SO_VIEW_LAYER:
+      if (space_outliner->show_restrict_flags & SO_RESTRICT_ENABLE) {
+        num_columns++;
+      }
       if (space_outliner->show_restrict_flags & SO_RESTRICT_HOLDOUT) {
         num_columns++;
       }
diff --git a/source/blender/editors/transform/transform_ops.c b/source/blender/editors/transform/transform_ops.c
index ab9548ad52e..2fa4c77f028 100644
--- a/source/blender/editors/transform/transform_ops.c
+++ b/source/blender/editors/transform/transform_ops.c
@@ -187,7 +187,7 @@ static int select_orientation_invoke(bContext *C,
 
   pup = UI_popup_menu_begin(C, IFACE_("Orientation"), ICON_NONE);
   layout = UI_popup_menu_layout(pup);
-  uiItemsEnumO(layout, "TRANSFORM_OT_select_orientation", "orientation");
+  uiItemsEnumO(layout, "TRANSFORM_OT_select_orientation", "orientation", false);
   UI_popup_menu_end(C, pup);
 
   return OPERATOR_INTERFACE;
diff --git a/source/blender/makesdna/DNA_collection_types.h b/source/blender/makesdna/DNA_collection_types.h
index 6cf02137fa6..1584642b449 100644
--- a/source/blender/makesdna/DNA_collection_types.h
+++ b/source/blender/makesdna/DNA_collection_types.h
@@ -58,7 +58,9 @@ typedef struct Collection {
   short flag;
   /* Runtime-only, always cleared on file load. */
   short tag;
-  char _pad[4];
+
+  short color;
+  char _pad[2];
 
   /* Runtime. Cache of objects in this collection and all its
    * children. This is created on demand when e.g. some physics
@@ -92,3 +94,16 @@ enum {
    * Using a generic tag like LIB_TAG_DOIT for this is just impossible, we need our very own. */
   COLLECTION_TAG_RELATION_REBUILD = (1 << 0),
 };
+
+/* Collection->color */
+enum {
+  COLLECTION_COLOR_NONE = 0,
+  COLLECTION_COLOR_01 = 1,
+  COLLECTION_COLOR_02 = 2,
+  COLLECTION_COLOR_03 = 3,
+  COLLECTION_COLOR_04 = 4,
+  COLLECTION_COLOR_05 = 5,
+  COLLECTION_COLOR_06 = 6,
+  COLLECTION_COLOR_07 = 7,
+  COLLECTION_COLOR_08 = 8,
+};
diff --git a/source/blender/makesdna/DNA_userdef_types.h b/source/blender/makesdna/DNA_userdef_types.h
index 136fe3744ef..2754304a582 100644
--- a/source/blender/makesdna/DNA_userdef_types.h
+++ b/source/blender/makesdna/DNA_userdef_types.h
@@ -455,6 +455,10 @@ typedef enum eWireColor_Flags {
   /* TH_WIRECOLOR_TEXTCOLS = (1 << 1), */ /* UNUSED */
 } eWireColor_Flags;
 
+typedef struct ThemeCollectionColor {
+  unsigned char color[4];
+} ThemeCollectionColor;
+
 /**
  * A theme.
  *
@@ -493,6 +497,8 @@ typedef struct bTheme {
   ThemeWireColor tarm[20];
   /*ThemeWireColor tobj[20];*/
 
+  ThemeCollectionColor collection_color[8];
+
   int active_theme_area;
   char _pad0[4];
 } bTheme;
diff --git a/source/blender/makesrna/RNA_access.h b/source/blender/makesrna/RNA_access.h
index 6acd9d16f80..ce4251d00ed 100644
--- a/source/blender/makesrna/RNA_access.h
+++ b/source/blender/makesrna/RNA_access.h
@@ -633,6 +633,7 @@ extern StructRNA RNA_TextureNodeViewer;
 extern StructRNA RNA_TextureSlot;
 extern StructRNA RNA_Theme;
 extern StructRNA RNA_ThemeBoneColorSet;
+extern StructRNA RNA_ThemeCollectionColor;
 extern StructRNA RNA_ThemeConsole;
 extern StructRNA RNA_ThemeDopeSheet;
 extern StructRNA RNA_ThemeFileBrowser;
diff --git a/source/blender/makesrna/RNA_enum_types.h b/source/blender/makesrna/RNA_enum_types.h
index fb9b62e729a..18af71d83db 100644
--- a/source/blender/makesrna/RNA_enum_types.h
+++ b/source/blender/makesrna/RNA_enum_types.h
@@ -229,6 +229,8 @@ extern const EnumPropertyItem rna_enum_context_mode_items[];
 extern const EnumPropertyItem rna_enum_curveprofile_preset_items[];
 extern const EnumPropertyItem rna_enum_preference_section_items[];
 
+extern const EnumPropertyItem rna_enum_collection_color_items[];
+
 /* API calls */
 int rna_node_tree_type_to_enum(struct bNodeTreeType *typeinfo);
 int rna_node_tree_idname_to_enum(const char *idname);
diff --git a/source/blender/makesrna/intern/rna_collection.c b/source/blender/makesrna/intern/rna_collection.c
index 9c6c95f2819..ecf7adfa925 100644
--- a/source/blender/makesrna/intern/rna_collection.c
+++ b/source/blender/makesrna/intern/rna_collection.c
@@ -30,6 +30,19 @@
 
 #include "WM_types.h"
 
+const EnumPropertyItem rna_enum_collection_color_items[] = {
+    {COLLECTION_COLOR_NONE, "NONE", ICON_X, "None", "Assign no color tag to the collection"},
+    {COLLECTION_COLOR_01, "COLOR_01", ICON_COLLECTION_COLOR_01, "Color 01", ""},
+    {COLLECTION_COLOR_02, "COLOR_02", ICON_COLLECTION_COLOR_02, "Color 02", ""},
+    {COLLECTION_COLOR_03, "COLOR_03", ICON_COLLECTION_COLOR_03, "Color 03", ""},
+    {COLLECTION_COLOR_04, "COLOR_04", ICON_COLLECTION_COLOR_04, "Color 04", ""},
+    {COLLECTION_COLOR_05, "COLOR_05", ICON_COLLECTION_COLOR_05, "Color 05", ""},
+    {COLLECTION_COLOR_06, "COLOR_06", ICON_COLLECTION_COLOR_06, "Color 06", ""},
+    {COLLECTION_COLOR_07, "COLOR_07", ICON_COLLECTION_COLOR_07, "Color 07", ""},
+    {COLLECTION_COLOR_08, "COLOR_08", ICON_COLLECTION_COLOR_08, "Color 08", ""},
+    {0, NULL, 0, NULL, NULL},
+};
+
 #ifdef RNA_RUNTIME
 
 #  include "DNA_object_types.h"
@@ -474,6 +487,12 @@ void RNA_def_collections(BlenderRNA *brna)
   RNA_def_property_ui_text(prop, "Disable in Renders", "Globally disable in renders");
   RNA_def_property_update(prop, NC_SCENE | ND_LAYER_CONTENT, "rna_Collection_flag_update");
 
+  prop = RNA_def_property(srna, "color", PROP_ENUM, PROP_NONE);
+  RNA_def_property_enum_sdna(prop, NULL, "color");
+  RNA_def_property_enum_items(prop, rna_enum_collection_color_items);
+  RNA_def_property_ui_text(prop, "Collection Color", "Color tag for a collection");
+  RNA_def_property_update(prop, NC_SCENE | ND_LAYER_CONTENT, NULL);
+
   RNA_define_lib_overridable(false);
 }
 
diff --git a/source/blender/makesrna/intern/rna_ui_api.c b/source/blender/makesrna/intern/rna_ui_api.c
index 8dfa54b95da..5c98044f975 100644
--- a/source/blender/makesrna/intern/rna_ui_api.c
+++ b/source/blender/makesrna/intern/rna_ui_api.c
@@ -977,6 +977,7 @@ void RNA_api_ui_layout(StructRNA *srna)
   RNA_def_parameter_flags(parm, 0, PARM_REQUIRED);
   parm = RNA_def_string(func, "property", NULL, 0, "", "Identifier of property in operator");
   RNA_def_parameter_flags(parm, 0, PARM_REQUIRED);
+  RNA_def_boolean(func, "icon_only", false, "", "Draw only icons in buttons, no text");
 
   func = RNA_def_function(srna, "operator_menu_enum", "rna_uiItemMenuEnumO");
   RNA_def_function_flag(func, FUNC_USE_CONTEXT);
diff --git a/source/blender/makesrna/intern/rna_userdef.c b/source/blender/makesrna/intern/rna_userdef.c
index 90873fa73f4..c5e08f3e54c 100644
--- a/source/blender/makesrna/intern/rna_userdef.c
+++ b/source/blender/makesrna/intern/rna_userdef.c
@@ -3615,6 +3615,23 @@ static void rna_def_userdef_theme_colorset(BlenderRNA *brna)
   RNA_def_property_update(prop, 0, "rna_userdef_theme_update");
 }
 
+static void rna_def_userdef_theme_collection_color(BlenderRNA *brna)
+{
+  StructRNA *srna;
+  PropertyRNA *prop;
+
+  srna = RNA_def_struct(brna, "ThemeCollectionColor", NULL);
+  RNA_def_struct_sdna(srna, "ThemeCollectionColor");
+  RNA_def_struct_clear_flag(srna, STRUCT_UNDO);
+  RNA_def_struct_ui_text(srna, "Theme Collection Color", "Theme settings for collection colors");
+
+  prop = RNA_def_property(srna, "color", PROP_FLOAT, PROP_COLOR_GAMMA);
+  RNA_def_property_float_sdna(prop, NULL, "color");
+  RNA_def_property_array(prop, 3);
+  RNA_def_property_ui_text(prop, "Color", "Collection Color Tag");
+  RNA_def_property_update(prop, 0, "rna_userdef_theme_update");
+}
+
 static void rna_def_userdef_theme_space_clip(BlenderRNA *brna)
 {
   StructRNA *srna;
@@ -3931,6 +3948,12 @@ static void rna_def_userdef_themes(BlenderRNA *brna)
   RNA_def_property_collection_sdna(prop, NULL, "tarm", "");
   RNA_def_property_struct_type(prop, "ThemeBoneColorSet");
   RNA_def_property_ui_text(prop, "Bone Color Sets", "");
+
+  prop = RNA_def_property(srna, "collection_color", PROP_COLLECTION, PROP_NONE);
+  RNA_def_property_flag(prop, PROP_NEVER_NULL);
+  RNA_def_property_collection_sdna(prop, NULL, "collection_color", "");
+  RNA_def_property_struct_type(prop, "ThemeCollectionColor");
+  RNA_def_property_ui_text(prop, "Collection Color", "");
 }
 
 static void rna_def_userdef_addon(BlenderRNA *brna)
@@ -4172,6 +4195,7 @@ static void rna_def_userdef_dothemes(BlenderRNA *brna)
   rna_def_userdef_theme_space_topbar(brna);
   rna_def_userdef_theme_space_statusbar(brna);
   rna_def_userdef_theme_colorset(brna);
+  rna_def_userdef_theme_collection_color(brna);
   rna_def_userdef_themes(brna);
 }
 
diff --git a/source/blender/windowmanager/intern/wm_operators.c b/source/blender/windowmanager/intern/wm_operators.c
index 9b25d660ff6..1fee0991372 100644
--- a/source/blender/windowmanager/intern/wm_operators.c
+++ b/source/blender/windowmanager/intern/wm_operators.c
@@ -3991,6 +3991,12 @@ static const EnumPropertyItem *rna_id_itemf(bContext *UNUSED(C),
     if (local == false || !ID_IS_LINKED(id)) {
       item_tmp.identifier = item_tmp.name = id->name + 2;
       item_tmp.value = i++;
+
+      /* Show collection color tag icons in menus. */
+      if (GS(id->name) == ID_GR) {
+        item_tmp.icon = UI_collection_color_icon_get((Collection *)id);
+      }
+
       RNA_enum_item_add(&item, &totitem, &item_tmp);
     }
   }