scripts/startup/bl_operators/wm.py

@@ -3494,6 +3494,76 @@ class WM_OT_drop_blend_file(Operator):
         col.operator("wm.append", text="Append...", icon='APPEND_BLEND').filepath = self.filepath
 
 
+class WM_FDT_alembic(bpy.types.FileDrop):
+    bl_space_type = "VIEW_3D"
+    bl_idname = "WM_FDT_alembic"
+    bl_operator = "WM_OT_alembic_import"
+
+    @classmethod
+    def poll_extension(cls, context, extension):
+        return extension == ".abc"
+
+
+class WM_FDT_collada(bpy.types.FileDrop):
+    bl_space_type = "VIEW_3D"
+    bl_idname = "WM_FDT_collada"
+    bl_operator = "WM_OT_collada_import"
+
+    @classmethod
+    def poll_extension(cls, context, extension):
+        return extension == ".dae"
+
+
+class WM_FDT_gpencil(bpy.types.FileDrop):
+    bl_space_type = "VIEW_3D"
+    bl_idname = "WM_FDT_gpencil"
+    bl_operator = "WM_OT_gpencil_import_svg"
+
+    @classmethod
+    def poll_extension(cls, context, extension):
+        return extension == ".svg"
+
+
+class WM_FDT_obj(bpy.types.FileDrop):
+    bl_space_type = "VIEW_3D"
+    bl_idname = "WM_FDT_obj"
+    bl_operator = "WM_OT_obj_import"
+
+    @classmethod
+    def poll_extension(cls, context, extension):
+        return extension == ".obj"
+
+
+class WM_FDT_ply(bpy.types.FileDrop):
+    bl_space_type = "VIEW_3D"
+    bl_idname = "WM_FDT_ply"
+    bl_operator = "WM_OT_ply_import"
+
+    @classmethod
+    def poll_extension(cls, context, extension):
+        return extension == ".ply"
+
+
+class WM_FDT_stl(bpy.types.FileDrop):
+    bl_space_type = "VIEW_3D"
+    bl_idname = "WM_FDT_stl"
+    bl_operator = "WM_OT_stl_import"
+
+    @classmethod
+    def poll_extension(cls, context, extension):
+        return extension == ".stl"
+
+
+class WM_FDT_usd(bpy.types.FileDrop):
+    bl_space_type = "VIEW_3D"
+    bl_idname = "WM_FDT_usd"
+    bl_operator = "WM_OT_usd_import"
+
+    @classmethod
+    def poll_extension(cls, context, extension):
+        return extension == ".usd"
+
+
 classes = (
     WM_OT_context_collection_boolean_set,
     WM_OT_context_cycle_array,
@@ -3539,5 +3609,13 @@ classes = (
     WM_MT_splash_quick_setup,
     WM_MT_splash,
     WM_MT_splash_about,
-    WM_MT_region_toggle_pie
+    WM_MT_region_toggle_pie,
+
+    WM_FDT_alembic,
+    WM_FDT_collada,
+    WM_FDT_gpencil,
+    WM_FDT_obj,
+    WM_FDT_ply,
+    WM_FDT_stl,
+    WM_FDT_usd,
 )

source/blender/blenkernel/BKE_screen.h

@@ -139,6 +139,9 @@ typedef struct SpaceType {
   /** Asset shelf type definitions. */
   ListBase asset_shelf_types; /* #AssetShelfType */
 
+  /** File drop type definitions. */
+  ListBase file_drop_types; /* #FileDropType */
+
   /* read and write... */
 
   /** Default key-maps to add. */
@@ -461,6 +464,28 @@ typedef struct AssetShelfType {
   ExtensionRNA rna_ext;
 } AssetShelfType;
 
+typedef struct FileDropType {
+  struct FileDropType *next, *prev;
+
+  char idname[BKE_ST_MAXNAME]; /* unique name */
+
+  char op_name[BKE_ST_MAXNAME]; /* operator name */
+
+  int space_type;
+
+  /** Determine if the operator can handle a specific file extension. */
+  bool (*poll_extension)(const struct bContext *C,
+                         FileDropType *file_drop_type,
+                         const char *extension);
+
+  /* RNA integration */
+  ExtensionRNA rna_ext;
+} FileDropType;
+
+typedef struct FileDrop {
+  struct FileDropType *type; /* runtime */
+} FileDrop;
+
 /* Space-types. */
 
 struct SpaceType *BKE_spacetype_from_id(int spaceid);

source/blender/blenkernel/intern/screen.cc

@@ -225,6 +225,7 @@ static void spacetype_free(SpaceType *st)
 
   BLI_freelistN(&st->regiontypes);
   BLI_freelistN(&st->asset_shelf_types);
+  BLI_freelistN(&st->file_drop_types);
 }
 
 void BKE_spacetypes_free()

source/blender/editors/interface/interface_drag.cc

@@ -64,7 +64,7 @@ void UI_but_drag_set_path(uiBut *but, const char *path)
   if (but->dragflag & UI_BUT_DRAGPOIN_FREE) {
     WM_drag_data_free(but->dragtype, but->dragpoin);
   }
-  but->dragpoin = WM_drag_create_path_data(path);
+  but->dragpoin = WM_drag_create_path_data(blender::Span(&path, 1));
   but->dragflag |= UI_BUT_DRAGPOIN_FREE;
 }
 

source/blender/editors/io/CMakeLists.txt

@@ -36,6 +36,8 @@ set(SRC
   io_ply_ops.cc
   io_stl_ops.cc
   io_usd.cc
+  io_utils.cc
+  io_drop_import_helper.cc
 
   io_alembic.hh
   io_cache.hh
@@ -46,6 +48,8 @@ set(SRC
   io_ply_ops.hh
   io_stl_ops.hh
   io_usd.hh
+  io_utils.hh
+  io_drop_import_helper.hh
 )
 
 set(LIB

source/blender/editors/io/io_alembic.cc

@@ -55,6 +55,8 @@
 
 #  include "ABC_alembic.h"
 
+#  include "io_utils.hh"
+
 const EnumPropertyItem rna_enum_abc_export_evaluation_mode_items[] = {
     {DAG_EVAL_RENDER,
      "RENDER",
@@ -584,8 +586,9 @@ static void ui_alembic_import_settings(uiLayout *layout, PointerRNA *imfptr)
   uiItemR(col, imfptr, "always_add_cache_reader", UI_ITEM_NONE, nullptr, ICON_NONE);
 }
 
-static void wm_alembic_import_draw(bContext * /*C*/, wmOperator *op)
+static void wm_alembic_import_draw(bContext *C, wmOperator *op)
 {
+  files_drop_label_draw(C, op, ICON_FILE_3D, ".abc");
   ui_alembic_import_settings(op->layout, op->ptr);
 }
 
@@ -595,7 +598,7 @@ static int wm_alembic_import_invoke(bContext *C, wmOperator *op, const wmEvent *
   if (!RNA_struct_property_is_set(op->ptr, "as_background_job")) {
     RNA_boolean_set(op->ptr, "as_background_job", true);
   }
-  return WM_operator_filesel(C, op, event);
+  return wm_io_import_invoke(C, op, event);
 }
 
 static int wm_alembic_import_exec(bContext *C, wmOperator *op)
@@ -651,7 +654,7 @@ void WM_OT_alembic_import(wmOperatorType *ot)
   ot->name = "Import Alembic";
   ot->description = "Load an Alembic archive";
   ot->idname = "WM_OT_alembic_import";
-  ot->flag = OPTYPE_REGISTER | OPTYPE_UNDO | OPTYPE_PRESET;
+  ot->flag = OPTYPE_UNDO | OPTYPE_PRESET;
 
   ot->invoke = wm_alembic_import_invoke;
   ot->exec = wm_alembic_import_exec;
@@ -665,6 +668,7 @@ void WM_OT_alembic_import(wmOperatorType *ot)
                                  WM_FILESEL_FILEPATH | WM_FILESEL_RELPATH | WM_FILESEL_SHOW_PROPS,
                                  FILE_DEFAULTDISPLAY,
                                  FILE_SORT_DEFAULT);
+  skip_filesel_props(ot, WM_FILESEL_FILEPATH | WM_FILESEL_RELPATH);
 
   PropertyRNA *prop = RNA_def_string(ot->srna, "filter_glob", "*.abc", 0, "", "");
   RNA_def_property_flag(prop, PROP_HIDDEN);

source/blender/editors/io/io_collada.cc

@@ -22,6 +22,7 @@
 
 #  include "ED_fileselect.hh"
 #  include "ED_object.hh"
+#  include "ED_outliner.hh"
 
 #  include "RNA_access.hh"
 #  include "RNA_define.hh"
@@ -35,6 +36,7 @@
 #  include "collada.h"
 
 #  include "io_collada.hh"
+#  include "io_utils.hh"
 
 static int wm_collada_export_invoke(bContext *C, wmOperator *op, const wmEvent * /*event*/)
 {
@@ -747,6 +749,11 @@ static int wm_collada_import_exec(bContext *C, wmOperator *op)
 
   if (collada_import(C, &import_settings)) {
     DEG_id_tag_update(&CTX_data_scene(C)->id, ID_RECALC_BASE_FLAGS);
+    Scene *scene = CTX_data_scene(C);
+    WM_event_add_notifier(C, NC_SCENE | ND_OB_SELECT, scene);
+    WM_event_add_notifier(C, NC_SCENE | ND_OB_ACTIVE, scene);
+    WM_event_add_notifier(C, NC_SCENE | ND_LAYER_CONTENT, scene);
+    ED_outliner_select_sync_from_object_tag(C);
     return OPERATOR_FINISHED;
   }
 
@@ -782,8 +789,9 @@ static void uiCollada_importSettings(uiLayout *layout, PointerRNA *imfptr)
   uiItemR(box, imfptr, "keep_bind_info", UI_ITEM_NONE, nullptr, ICON_NONE);
 }
 
-static void wm_collada_import_draw(bContext * /*C*/, wmOperator *op)
+static void wm_collada_import_draw(bContext *C, wmOperator *op)
 {
+  files_drop_label_draw(C, op, ICON_FILE_3D, "dae");
   uiCollada_importSettings(op->layout, op->ptr);
 }
 
@@ -792,9 +800,9 @@ void WM_OT_collada_import(wmOperatorType *ot)
   ot->name = "Import COLLADA";
   ot->description = "Load a Collada file";
   ot->idname = "WM_OT_collada_import";
-  ot->flag = OPTYPE_REGISTER | OPTYPE_UNDO | OPTYPE_PRESET;
+  ot->flag = OPTYPE_UNDO | OPTYPE_PRESET;
 
-  ot->invoke = WM_operator_filesel;
+  ot->invoke = wm_io_import_invoke;
   ot->exec = wm_collada_import_exec;
   ot->poll = WM_operator_winactive;
 
@@ -807,6 +815,7 @@ void WM_OT_collada_import(wmOperatorType *ot)
                                  WM_FILESEL_FILEPATH | WM_FILESEL_SHOW_PROPS,
                                  FILE_DEFAULTDISPLAY,
                                  FILE_SORT_DEFAULT);
+  skip_filesel_props(ot, WM_FILESEL_FILEPATH);
 
   PropertyRNA *prop = RNA_def_string(ot->srna, "filter_glob", "*.dae", 0, "", "");
   RNA_def_property_flag(prop, PROP_HIDDEN);

source/blender/editors/io/io_drop_import_helper.cc

@@ -0,0 +1,155 @@
+/* SPDX-License-Identifier: GPL-2.0-or-later */
+
+#include "DNA_space_types.h"
+
+#include "BLI_blenlib.h"
+#include "BLI_utildefines.h"
+
+#include "BKE_context.h"
+#include "BKE_main.h"
+#include "BKE_preferences.h"
+#include "BKE_screen.h"
+
+#include "ED_fileselect.hh"
+
+#include "RNA_access.hh"
+#include "RNA_define.hh"
+
+#include "WM_api.hh"
+#include "WM_types.hh"
+
+#include "io_drop_import_helper.hh"
+
+static wmOperatorType *get_operator_type_for_extension(const bContext *C, const char *extension)
+{
+  ScrArea *area = CTX_wm_area(C);
+  SpaceType *st = area->type;
+
+  FileDropType *file_drop_type = nullptr;
+
+  LISTBASE_FOREACH (FileDropType *, file_drop_test, &st->file_drop_types) {
+    if (file_drop_test->poll_extension &&
+        file_drop_test->poll_extension(C, file_drop_test, extension)) {
+      file_drop_type = file_drop_test;
+    }
+  };
+  return file_drop_type ? WM_operatortype_find(file_drop_type->op_name, false) : nullptr;
+}
+
+static int wm_drop_import_helper_exec(bContext *C, wmOperator *op)
+{
+  char extension[MAX_NAME];
+  RNA_string_get(op->ptr, "extension", extension);
+
+  wmOperatorType *ot = get_operator_type_for_extension(C, extension);
+
+  if (!ot) {
+    return OPERATOR_CANCELLED;
+  }
+
+  PointerRNA op_props;
+  WM_operator_properties_create_ptr(&op_props, ot);
+
+  char filepath[FILE_MAX];
+  if (RNA_struct_find_property(&op_props, "filepath")) {
+    RNA_string_get(op->ptr, "filepath", filepath);
+    RNA_string_set(&op_props, "filepath", filepath);
+  }
+
+  if (RNA_struct_find_property(&op_props, "directory")) {
+    RNA_string_get(op->ptr, "directory", filepath);
+    RNA_string_set(&op_props, "directory", filepath);
+
+    RNA_collection_clear(&op_props, "files");
+    int files_len = RNA_collection_length(op->ptr, "files");
+    PropertyRNA *prop = RNA_struct_find_property(op->ptr, "files");
+
+    for (int i = 0; i < files_len; i++) {
+      PointerRNA fileptr;
+      RNA_property_collection_lookup_int(op->ptr, prop, i, &fileptr);
+      RNA_string_get(&fileptr, "name", filepath);
+
+      PointerRNA itemptr{};
+      RNA_collection_add(&op_props, "files", &itemptr);
+      RNA_string_set(&itemptr, "name", filepath);
+    }
+  }
+
+  WM_operator_name_call_ptr(C, ot, WM_OP_INVOKE_DEFAULT, &op_props, nullptr);
+  WM_operator_properties_free(&op_props);
+  return OPERATOR_FINISHED;
+}
+
+void WM_OT_drop_import_helper(wmOperatorType *ot)
+{
+  ot->name = "Drop Import Herlper";
+  ot->description =
+      "Helper operator that handles file drops events and calls operators that can import files "
+      "with extension";
+  ot->idname = "WM_OT_drop_import_helper";
+
+  ot->exec = wm_drop_import_helper_exec;
+  PropertyRNA *prop;
+
+  prop = RNA_def_string(ot->srna, "extension", nullptr, MAX_NAME, "extension", "extension");
+  RNA_def_property_flag(prop, PROP_HIDDEN | PROP_SKIP_SAVE);
+
+  WM_operator_properties_filesel(ot,
+                                 FILE_TYPE_FOLDER,
+                                 FILE_BLENDER,
+                                 FILE_OPENFILE,
+                                 WM_FILESEL_FILEPATH | WM_FILESEL_FILES | WM_FILESEL_DIRECTORY |
+                                     WM_FILESEL_SHOW_PROPS,
+                                 FILE_DEFAULTDISPLAY,
+                                 FILE_SORT_DEFAULT);
+}
+
+void files_drop_copy(bContext * /*C*/, wmDrag *drag, wmDropBox *drop)
+{
+  const auto paths = WM_drag_get_paths(drag);
+  RNA_string_set(drop->ptr, "filepath", paths[0].c_str());
+
+  char dir[FILE_MAX], file[FILE_MAX];
+  RNA_string_set(drop->ptr, "extension", BLI_path_extension(paths[0].c_str()));
+
+  BLI_path_split_dir_file(paths[0].c_str(), dir, sizeof(dir), file, sizeof(file));
+  RNA_string_set(drop->ptr, "directory", dir);
+
+  RNA_collection_clear(drop->ptr, "files");
+  for (const auto &path : paths) {
+    BLI_path_split_dir_file(path.c_str(), dir, sizeof(dir), file, sizeof(file));
+
+    PointerRNA itemptr{};
+    RNA_collection_add(drop->ptr, "files", &itemptr);
+    RNA_string_set(&itemptr, "name", file);
+  }
+}
+
+static bool poll(bContext *C, wmDrag *drag, const wmEvent * /*event*/)
+{
+  if (drag->type != WM_DRAG_PATH) {
+    return false;
+  }
+  const auto paths = WM_drag_get_paths(drag);
+  const char *extension = BLI_path_extension(paths[0].c_str());
+
+  return extension && get_operator_type_for_extension(C, extension);
+}
+static char *tooltip(bContext *C, wmDrag *drag, const int /*xy*/[2], wmDropBox * /*drop*/)
+{
+  const auto paths = WM_drag_get_paths(drag);
+  const char *extension = BLI_path_extension(paths[0].c_str());
+
+  wmOperatorType *ot = get_operator_type_for_extension(C, extension);
+
+  if (!ot || (!ot->name || !ot->description)) {
+    return nullptr;
+  }
+  return BLI_strdup(ot->name ? ot->name : ot->description);
+}
+
+void ED_dropbox_import_helper()
+{
+  ListBase *lb = WM_dropboxmap_find("Window", 0, 0);
+  WM_dropbox_add(lb, "WM_OT_drop_import_helper", poll, files_drop_copy, nullptr, tooltip);
+}

source/blender/editors/io/io_drop_import_helper.hh

@@ -0,0 +1,8 @@
+/* SPDX-License-Identifier: GPL-2.0-or-later */
+
+#pragma once
+
+struct wmOperatorType;
+
+void WM_OT_drop_import_helper(wmOperatorType *ot);
+void ED_dropbox_import_helper();

source/blender/editors/io/io_gpencil_import.cc

@@ -36,6 +36,7 @@
 #  include "ED_gpencil_legacy.hh"
 
 #  include "io_gpencil.hh"
+#  include "io_utils.hh"
 
 #  include "gpencil_io.h"
 
@@ -55,13 +56,6 @@ static bool wm_gpencil_import_svg_common_check(bContext * /*C*/, wmOperator *op)
   return false;
 }
 
-static int wm_gpencil_import_svg_invoke(bContext *C, wmOperator *op, const wmEvent * /*event*/)
-{
-  WM_event_add_fileselect(C, op);
-
-  return OPERATOR_RUNNING_MODAL;
-}
-
 static int wm_gpencil_import_svg_exec(bContext *C, wmOperator *op)
 {
   Scene *scene = CTX_data_scene(C);
@@ -136,13 +130,15 @@ static void ui_gpencil_import_svg_settings(uiLayout *layout, PointerRNA *imfptr)
 {
   uiLayoutSetPropSep(layout, true);
   uiLayoutSetPropDecorate(layout, false);
-  uiLayout *col = uiLayoutColumn(layout, false);
+  uiLayout *box = uiLayoutBox(layout);
+  uiLayout *col = uiLayoutColumn(box, false);
   uiItemR(col, imfptr, "resolution", UI_ITEM_NONE, nullptr, ICON_NONE);
   uiItemR(col, imfptr, "scale", UI_ITEM_NONE, nullptr, ICON_NONE);
 }
 
-static void wm_gpencil_import_svg_draw(bContext * /*C*/, wmOperator *op)
+static void wm_gpencil_import_svg_draw(bContext *C, wmOperator *op)
 {
+  files_drop_label_draw(C, op, ICON_FILE_3D, ".svg");
   ui_gpencil_import_svg_settings(op->layout, op->ptr);
 }
 
@@ -161,7 +157,7 @@ void WM_OT_gpencil_import_svg(wmOperatorType *ot)
   ot->description = "Import SVG into grease pencil";
   ot->idname = "WM_OT_gpencil_import_svg";
 
-  ot->invoke = wm_gpencil_import_svg_invoke;
+  ot->invoke = wm_io_import_invoke;
   ot->exec = wm_gpencil_import_svg_exec;
   ot->poll = wm_gpencil_import_svg_poll;
   ot->ui = wm_gpencil_import_svg_draw;
@@ -175,6 +171,8 @@ void WM_OT_gpencil_import_svg(wmOperatorType *ot)
                                      WM_FILESEL_DIRECTORY | WM_FILESEL_FILES,
                                  FILE_DEFAULTDISPLAY,
                                  FILE_SORT_DEFAULT);
+  skip_filesel_props(
+      ot, WM_FILESEL_FILEPATH | WM_FILESEL_RELPATH | WM_FILESEL_DIRECTORY | WM_FILESEL_FILES);
 
   RNA_def_int(ot->srna,
               "resolution",

source/blender/editors/io/io_obj.cc

@@ -41,6 +41,7 @@
 #  include "IO_wavefront_obj.h"
 
 #  include "io_obj.hh"
+#  include "io_utils.hh"
 
 static const EnumPropertyItem io_obj_export_evaluation_mode[] = {
     {DAG_EVAL_RENDER, "DAG_EVAL_RENDER", 0, "Render", "Export objects as they appear in render"},
@@ -386,12 +387,6 @@ void WM_OT_obj_export(wmOperatorType *ot)
   RNA_def_property_flag(prop, PROP_HIDDEN);
 }
 
-static int wm_obj_import_invoke(bContext *C, wmOperator *op, const wmEvent * /*event*/)
-{
-  WM_event_add_fileselect(C, op);
-  return OPERATOR_RUNNING_MODAL;
-}
-
 static int wm_obj_import_exec(bContext *C, wmOperator *op)
 {
   OBJImportParams import_params{};
@@ -473,6 +468,7 @@ static void wm_obj_import_draw(bContext *C, wmOperator *op)
   PointerRNA ptr;
   wmWindowManager *wm = CTX_wm_manager(C);
   RNA_pointer_create(&wm->id, op->type->srna, op->properties, &ptr);
+  files_drop_label_draw(C, op, ICON_FILE_3D, ".obj");
   ui_obj_import_settings(op->layout, &ptr);
 }
 
@@ -483,9 +479,9 @@ void WM_OT_obj_import(wmOperatorType *ot)
   ot->name = "Import Wavefront OBJ";
   ot->description = "Load a Wavefront OBJ scene";
   ot->idname = "WM_OT_obj_import";
-  ot->flag = OPTYPE_REGISTER | OPTYPE_UNDO | OPTYPE_PRESET;
+  ot->flag = OPTYPE_UNDO | OPTYPE_PRESET;
 
-  ot->invoke = wm_obj_import_invoke;
+  ot->invoke = wm_io_import_invoke;
   ot->exec = wm_obj_import_exec;
   ot->poll = WM_operator_winactive;
   ot->ui = wm_obj_import_draw;
@@ -499,6 +495,8 @@ void WM_OT_obj_import(wmOperatorType *ot)
                                  FILE_DEFAULTDISPLAY,
                                  FILE_SORT_DEFAULT);
 
+  skip_filesel_props(ot, WM_FILESEL_FILEPATH | WM_FILESEL_DIRECTORY | WM_FILESEL_FILES);
+
   RNA_def_float(
       ot->srna,
       "global_scale",

source/blender/editors/io/io_ops.cc

@@ -23,6 +23,7 @@
 #endif
 
 #include "io_cache.hh"
+#include "io_drop_import_helper.hh"
 #include "io_gpencil.hh"
 #include "io_obj.hh"
 #include "io_ply_ops.hh"
@@ -73,4 +74,6 @@ void ED_operatortypes_io()
 #ifdef WITH_IO_STL
   WM_operatortype_append(WM_OT_stl_import);
 #endif
+  WM_operatortype_append(WM_OT_drop_import_helper);
+  ED_dropbox_import_helper();
 }

source/blender/editors/io/io_ply_ops.cc

@@ -37,6 +37,7 @@
 
 #  include "IO_ply.h"
 #  include "io_ply_ops.hh"
+#  include "io_utils.hh"
 
 static const EnumPropertyItem ply_vertex_colors_mode[] = {
     {PLY_VERTEX_COLOR_NONE, "NONE", 0, "None", "Do not import/export color attributes"},
@@ -231,11 +232,6 @@ void WM_OT_ply_export(wmOperatorType *ot)
   RNA_def_property_flag(prop, PROP_HIDDEN);
 }
 
-static int wm_ply_import_invoke(bContext *C, wmOperator *op, const wmEvent *event)
-{
-  return WM_operator_filesel(C, op, event);
-}
-
 static int wm_ply_import_exec(bContext *C, wmOperator *op)
 {
   PLYImportParams params{};
@@ -280,6 +276,30 @@ static int wm_ply_import_exec(bContext *C, wmOperator *op)
   return OPERATOR_FINISHED;
 }
 
+static void ui_ply_import_settings(uiLayout *layout, PointerRNA *imfptr)
+{
+  uiLayoutSetPropSep(layout, true);
+  uiLayoutSetPropDecorate(layout, false);
+
+  uiLayout *box = uiLayoutBox(layout);
+  uiLayout *col = uiLayoutColumn(box, false);
+  uiItemR(col, imfptr, "global_scale", UI_ITEM_NONE, NULL, ICON_NONE);
+  uiItemR(col, imfptr, "use_scene_unit", UI_ITEM_NONE, NULL, ICON_NONE);
+  uiItemR(col, imfptr, "forward_axis", UI_ITEM_NONE, IFACE_("Forward Axis"), ICON_NONE);
+  uiItemR(col, imfptr, "up_axis", UI_ITEM_NONE, NULL, ICON_NONE);
+  uiItemR(col, imfptr, "merge_verts", UI_ITEM_NONE, NULL, ICON_NONE);
+  uiItemR(col, imfptr, "import_colors", UI_ITEM_NONE, NULL, ICON_NONE);
+}
+
+static void wm_ply_import_draw(bContext *C, wmOperator *op)
+{
+  PointerRNA ptr;
+  wmWindowManager *wm = CTX_wm_manager(C);
+  RNA_pointer_create(&wm->id, op->type->srna, op->properties, &ptr);
+  files_drop_label_draw(C, op, ICON_FILE_3D, ".ply");
+  ui_ply_import_settings(op->layout, &ptr);
+}
+
 void WM_OT_ply_import(wmOperatorType *ot)
 {
   PropertyRNA *prop;
@@ -288,10 +308,11 @@ void WM_OT_ply_import(wmOperatorType *ot)
   ot->description = "Import an PLY file as an object";
   ot->idname = "WM_OT_ply_import";
 
-  ot->invoke = wm_ply_import_invoke;
+  ot->invoke = wm_io_import_invoke;
   ot->exec = wm_ply_import_exec;
   ot->poll = WM_operator_winactive;
-  ot->flag = OPTYPE_REGISTER | OPTYPE_UNDO | OPTYPE_PRESET;
+  ot->ui = wm_ply_import_draw;
+  ot->flag = OPTYPE_UNDO | OPTYPE_PRESET;
 
   WM_operator_properties_filesel(ot,
                                  FILE_TYPE_FOLDER,
@@ -301,6 +322,7 @@ void WM_OT_ply_import(wmOperatorType *ot)
                                      WM_FILESEL_SHOW_PROPS,
                                  FILE_DEFAULTDISPLAY,
                                  FILE_SORT_DEFAULT);
+  skip_filesel_props(ot, WM_FILESEL_FILEPATH | WM_FILESEL_FILES | WM_FILESEL_DIRECTORY);
 
   RNA_def_float(ot->srna, "global_scale", 1.0f, 1e-6f, 1e6f, "Scale", "", 0.001f, 1000.0f);
   RNA_def_boolean(ot->srna,

source/blender/editors/io/io_stl_ops.cc

@@ -8,6 +8,8 @@
 
 #ifdef WITH_IO_STL
 
+#  include "BLT_translation.h"
+
 #  include "BKE_context.h"
 #  include "BKE_report.h"
 
@@ -21,13 +23,12 @@
 #  include "RNA_access.hh"
 #  include "RNA_define.hh"
 
+#  include "UI_interface.hh"
+#  include "UI_resources.hh"
+
 #  include "IO_stl.h"
 #  include "io_stl_ops.hh"
-
-static int wm_stl_import_invoke(bContext *C, wmOperator *op, const wmEvent *event)
-{
-  return WM_operator_filesel(C, op, event);
-}
+#  include "io_utils.hh"
 
 static int wm_stl_import_exec(bContext *C, wmOperator *op)
 {
@@ -85,6 +86,29 @@ static bool wm_stl_import_check(bContext * /*C*/, wmOperator *op)
   }
   return false;
 }
+static void ui_stl_import_settings(uiLayout *layout, PointerRNA *imfptr)
+{
+  uiLayoutSetPropSep(layout, true);
+  uiLayoutSetPropDecorate(layout, false);
+
+  uiLayout *box = uiLayoutBox(layout);
+  uiLayout *col = uiLayoutColumn(box, false);
+  uiItemR(col, imfptr, "global_scale", UI_ITEM_NONE, NULL, ICON_NONE);
+  uiItemR(col, imfptr, "use_scene_unit", UI_ITEM_NONE, NULL, ICON_NONE);
+  uiItemR(col, imfptr, "use_facet_normal", UI_ITEM_NONE, NULL, ICON_NONE);
+  uiItemR(col, imfptr, "forward_axis", UI_ITEM_NONE, IFACE_("Forward Axis"), ICON_NONE);
+  uiItemR(col, imfptr, "up_axis", UI_ITEM_NONE, NULL, ICON_NONE);
+  uiItemR(col, imfptr, "use_mesh_validate", UI_ITEM_NONE, NULL, ICON_NONE);
+}
+
+static void wm_stl_import_draw(bContext *C, wmOperator *op)
+{
+  PointerRNA ptr;
+  wmWindowManager *wm = CTX_wm_manager(C);
+  RNA_pointer_create(&wm->id, op->type->srna, op->properties, &ptr);
+  files_drop_label_draw(C, op, ICON_FILE_3D, ".stl");
+  ui_stl_import_settings(op->layout, &ptr);
+}
 
 void WM_OT_stl_import(wmOperatorType *ot)
 {
@@ -94,11 +118,12 @@ void WM_OT_stl_import(wmOperatorType *ot)
   ot->description = "Import an STL file as an object";
   ot->idname = "WM_OT_stl_import";
 
-  ot->invoke = wm_stl_import_invoke;
+  ot->invoke = wm_io_import_invoke;
   ot->exec = wm_stl_import_exec;
   ot->poll = WM_operator_winactive;
   ot->check = wm_stl_import_check;
-  ot->flag = OPTYPE_REGISTER | OPTYPE_UNDO | OPTYPE_PRESET;
+  ot->ui = wm_stl_import_draw;
+  ot->flag = OPTYPE_UNDO | OPTYPE_PRESET;
 
   WM_operator_properties_filesel(ot,
                                  FILE_TYPE_FOLDER,
@@ -108,6 +133,7 @@ void WM_OT_stl_import(wmOperatorType *ot)
                                      WM_FILESEL_SHOW_PROPS,
                                  FILE_DEFAULTDISPLAY,
                                  FILE_SORT_DEFAULT);
+  skip_filesel_props(ot, WM_FILESEL_FILEPATH | WM_FILESEL_FILES | WM_FILESEL_DIRECTORY);
 
   RNA_def_float(ot->srna, "global_scale", 1.0f, 1e-6f, 1e6f, "Scale", "", 0.001f, 1000.0f);
   RNA_def_boolean(ot->srna,

source/blender/editors/io/io_usd.cc

@@ -42,6 +42,7 @@
 #  include "DEG_depsgraph.h"
 
 #  include "io_usd.hh"
+#  include "io_utils.hh"
 #  include "usd.h"
 
 #  include <cstdio>
@@ -386,7 +387,7 @@ static int wm_usd_import_invoke(bContext *C, wmOperator *op, const wmEvent *even
   options->as_background_job = true;
   op->customdata = options;
 
-  return WM_operator_filesel(C, op, event);
+  return wm_io_import_invoke(C, op, event);
 }
 
 static int wm_usd_import_exec(bContext *C, wmOperator *op)
@@ -525,11 +526,13 @@ static void wm_usd_import_cancel(bContext * /*C*/, wmOperator *op)
   free_operator_customdata(op);
 }
 
-static void wm_usd_import_draw(bContext * /*C*/, wmOperator *op)
+static void wm_usd_import_draw(bContext *C, wmOperator *op)
 {
   uiLayout *layout = op->layout;
   PointerRNA *ptr = op->ptr;
 
+  files_drop_label_draw(C, op, ICON_FILE_3D, ".usd");
+
   uiLayoutSetPropSep(layout, true);
   uiLayoutSetPropDecorate(layout, false);
 
@@ -601,7 +604,7 @@ void WM_OT_usd_import(wmOperatorType *ot)
   ot->poll = WM_operator_winactive;
   ot->ui = wm_usd_import_draw;
 
-  ot->flag = OPTYPE_REGISTER | OPTYPE_UNDO | OPTYPE_PRESET;
+  ot->flag = OPTYPE_UNDO | OPTYPE_PRESET;
 
   WM_operator_properties_filesel(ot,
                                  FILE_TYPE_FOLDER | FILE_TYPE_USD,
@@ -610,6 +613,7 @@ void WM_OT_usd_import(wmOperatorType *ot)
                                  WM_FILESEL_FILEPATH | WM_FILESEL_RELPATH | WM_FILESEL_SHOW_PROPS,
                                  FILE_DEFAULTDISPLAY,
                                  FILE_SORT_DEFAULT);
+  skip_filesel_props(ot, WM_FILESEL_FILEPATH | WM_FILESEL_RELPATH);
 
   PropertyRNA *prop = RNA_def_string(ot->srna, "filter_glob", "*.usd", 0, "", "");
   RNA_def_property_flag(prop, PROP_HIDDEN);

source/blender/editors/io/io_utils.cc

@@ -0,0 +1,85 @@
+/* SPDX-License-Identifier: GPL-2.0-or-later */
+
+#if defined(WITH_COLLADA) || defined(WITH_IO_GPENCIL) || defined(WITH_IO_WAVEFRONT_OBJ) || \
+    defined(WITH_IO_PLY) || defined(WITH_IO_STL) || defined(WITH_USD)
+
+#  include "BKE_context.h"
+
+#  include "BLI_path_util.h"
+#  include "BLI_string.h"
+#  include "BLI_utildefines.h"
+
+#  include "BLT_translation.h"
+
+#  include "DNA_space_types.h"
+
+#  include "ED_fileselect.hh"
+
+#  include "RNA_access.hh"
+#  include "RNA_define.hh"
+
+#  include "UI_interface.hh"
+
+#  include "WM_api.hh"
+
+#  include "io_utils.hh"
+
+int wm_io_import_invoke(bContext *C, wmOperator *op, const wmEvent * /* event */)
+{
+  char filepath[FILE_MAX];
+  RNA_string_get(op->ptr, "filepath", filepath);
+
+  if (filepath[0]) {
+    return WM_operator_props_dialog_popup(C, op, 300);
+  }
+
+  WM_event_add_fileselect(C, op);
+  return OPERATOR_RUNNING_MODAL;
+}
+
+void skip_filesel_props(wmOperatorType *ot, const eFileSel_Flag flag)
+{
+  PropertyRNA *prop;
+  if (flag & WM_FILESEL_FILEPATH) {
+    prop = RNA_struct_type_find_property(ot->srna, "filepath");
+    RNA_def_property_flag(prop, PROP_SKIP_SAVE);
+  }
+  if (flag & WM_FILESEL_FILENAME) {
+    prop = RNA_struct_type_find_property(ot->srna, "filename");
+    RNA_def_property_flag(prop, PROP_SKIP_SAVE);
+  }
+  if (flag & WM_FILESEL_DIRECTORY) {
+    prop = RNA_struct_type_find_property(ot->srna, "directory");
+    RNA_def_property_flag(prop, PROP_SKIP_SAVE);
+  }
+  if (flag & WM_FILESEL_FILES) {
+    prop = RNA_struct_type_find_property(ot->srna, "files");
+    RNA_def_property_flag(prop, PROP_SKIP_SAVE);
+  }
+  if (flag & WM_FILESEL_RELPATH) {
+    prop = RNA_struct_type_find_property(ot->srna, "relative_path");
+    RNA_def_property_flag(prop, PROP_SKIP_SAVE);
+  }
+}
+
+void files_drop_label_draw(bContext *C, wmOperator *op, int icon, const char *extension)
+{
+  ScrArea *area = CTX_wm_area(C);
+
+  if (area->spacetype == SPACE_FILE) {
+    return;
+  }
+
+  char label[FILE_MAX];
+  RNA_string_get(op->ptr, "filepath", label);
+
+  if (RNA_struct_find_property(op->ptr, "directory") &&
+      RNA_collection_length(op->ptr, "files") > 1) {
+    sprintf(label, "%d %s files dropped.", RNA_collection_length(op->ptr, "files"), extension);
+  }
+
+  uiLayout *box = uiLayoutBox(op->layout);
+  uiItemL(box, label, icon);
+}
+
+#endif

source/blender/editors/io/io_utils.hh

@@ -0,0 +1,19 @@
+/* SPDX-License-Identifier: GPL-2.0-or-later */
+
+#pragma once
+
+#if defined(WITH_COLLADA) || defined(WITH_IO_GPENCIL) || defined(WITH_IO_WAVEFRONT_OBJ) || \
+    defined(WITH_IO_PLY) || defined(WITH_IO_STL) || defined(WITH_USD)
+
+#  include "WM_types.hh"
+
+struct wmOperator;
+struct wmOperatorType;
+struct wmDrag;
+struct wmDropBox;
+
+int wm_io_import_invoke(bContext *C, wmOperator *op, const wmEvent *event);
+void skip_filesel_props(wmOperatorType *ot, const eFileSel_Flag flag);
+void files_drop_label_draw(bContext *C, wmOperator *op, int icon, const char *extension);
+
+#endif

source/blender/editors/screen/screen_ops.cc

@@ -5913,7 +5913,7 @@ static bool blend_file_drop_poll(bContext * /*C*/, wmDrag *drag, const wmEvent *
 static void blend_file_drop_copy(bContext * /*C*/, wmDrag *drag, wmDropBox *drop)
 {
   /* copy drag path to properties */
-  RNA_string_set(drop->ptr, "filepath", WM_drag_get_path(drag));
+  RNA_string_set(drop->ptr, "filepath", WM_drag_get_paths(drag)[0].c_str());
 }
 
 void ED_keymap_screen(wmKeyConfig *keyconf)

source/blender/editors/space_clip/space_clip.cc

@@ -536,7 +536,8 @@ static void clip_drop_copy(bContext * /*C*/, wmDrag *drag, wmDropBox *drop)
   PointerRNA itemptr;
   char dir[FILE_MAX], file[FILE_MAX];
 
-  BLI_path_split_dir_file(WM_drag_get_path(drag), dir, sizeof(dir), file, sizeof(file));
+  BLI_path_split_dir_file(
+      WM_drag_get_paths(drag)[0].c_str(), dir, sizeof(dir), file, sizeof(file));
 
   RNA_string_set(drop->ptr, "directory", dir);
 

source/blender/editors/space_console/space_console.cc

@@ -174,7 +174,7 @@ static bool path_drop_poll(bContext * /*C*/, wmDrag *drag, const wmEvent * /*eve
 static void path_drop_copy(bContext * /*C*/, wmDrag *drag, wmDropBox *drop)
 {
   char pathname[FILE_MAX + 2];
-  SNPRINTF(pathname, "\"%s\"", WM_drag_get_path(drag));
+  SNPRINTF(pathname, "\"%s\"", WM_drag_get_paths(drag)[0].c_str());
   RNA_string_set(drop->ptr, "text", pathname);
 }
 

source/blender/editors/space_file/space_file.cc

@@ -800,7 +800,7 @@ static bool filepath_drop_poll(bContext *C, wmDrag *drag, const wmEvent * /*even
 
 static void filepath_drop_copy(bContext * /*C*/, wmDrag *drag, wmDropBox *drop)
 {
-  RNA_string_set(drop->ptr, "filepath", WM_drag_get_path(drag));
+  RNA_string_set(drop->ptr, "filepath", WM_drag_get_paths(drag)[0].c_str());
 }
 
 /* region dropbox definition */

source/blender/editors/space_image/space_image.cc

@@ -268,7 +268,7 @@ static bool image_drop_poll(bContext *C, wmDrag *drag, const wmEvent *event)
 static void image_drop_copy(bContext * /*C*/, wmDrag *drag, wmDropBox *drop)
 {
   /* copy drag path to properties */
-  RNA_string_set(drop->ptr, "filepath", WM_drag_get_path(drag));
+  RNA_string_set(drop->ptr, "filepath", WM_drag_get_paths(drag)[0].c_str());
 }
 
 /* area+region dropbox definition */

source/blender/editors/space_node/space_node.cc

@@ -726,9 +726,9 @@ static void node_id_path_drop_copy(bContext *C, wmDrag *drag, wmDropBox *drop)
     return;
   }
 
-  const char *path = WM_drag_get_path(drag);
-  if (path) {
-    RNA_string_set(drop->ptr, "filepath", path);
+  const auto paths = WM_drag_get_paths(drag);
+  if (paths.begin()) {
+    RNA_string_set(drop->ptr, "filepath", paths[0].c_str());
     RNA_struct_property_unset(drop->ptr, "name");
     return;
   }

source/blender/editors/space_sequencer/sequencer_drag_drop.cc

@@ -249,17 +249,17 @@ static void sequencer_drop_copy(bContext *C, wmDrag *drag, wmDropBox *drop)
     return;
   }
 
-  const char *path = WM_drag_get_path(drag);
+  const auto paths = WM_drag_get_paths(drag);
   /* Path dropped. */
-  if (path) {
+  if (paths.begin()) {
     if (RNA_struct_find_property(drop->ptr, "filepath")) {
-      RNA_string_set(drop->ptr, "filepath", path);
+      RNA_string_set(drop->ptr, "filepath", paths[0].c_str());
     }
     if (RNA_struct_find_property(drop->ptr, "directory")) {
       PointerRNA itemptr;
       char dir[FILE_MAX], file[FILE_MAX];
 
-      BLI_path_split_dir_file(path, dir, sizeof(dir), file, sizeof(file));
+      BLI_path_split_dir_file(paths[0].c_str(), dir, sizeof(dir), file, sizeof(file));
 
       RNA_string_set(drop->ptr, "directory", dir);
 
@@ -337,7 +337,7 @@ static void get_drag_path(const bContext *C, wmDrag *drag, char r_path[FILE_MAX]
     BLI_path_abs(r_path, BKE_main_blendfile_path_from_global());
   }
   else {
-    BLI_strncpy(r_path, WM_drag_get_path(drag), FILE_MAX);
+    BLI_strncpy(r_path, WM_drag_get_paths(drag)[0].c_str(), FILE_MAX);
   }
 }
 

source/blender/editors/space_text/space_text.cc

@@ -316,7 +316,7 @@ static bool text_drop_poll(bContext * /*C*/, wmDrag *drag, const wmEvent * /*eve
 static void text_drop_copy(bContext * /*C*/, wmDrag *drag, wmDropBox *drop)
 {
   /* copy drag path to properties */
-  RNA_string_set(drop->ptr, "filepath", WM_drag_get_path(drag));
+  RNA_string_set(drop->ptr, "filepath", WM_drag_get_paths(drag)[0].c_str());
 }
 
 static bool text_drop_paste_poll(bContext * /*C*/, wmDrag *drag, const wmEvent * /*event*/)

source/blender/editors/space_view3d/space_view3d.cc

@@ -929,9 +929,9 @@ static void view3d_id_path_drop_copy(bContext *C, wmDrag *drag, wmDropBox *drop)
     RNA_struct_property_unset(drop->ptr, "filepath");
     return;
   }
-  const char *path = WM_drag_get_path(drag);
-  if (path) {
-    RNA_string_set(drop->ptr, "filepath", path);
+  const auto paths = WM_drag_get_paths(drag);
+  if (paths.begin()) {
+    RNA_string_set(drop->ptr, "filepath", paths[0].c_str());
     RNA_struct_property_unset(drop->ptr, "image");
   }
 }

source/blender/makesrna/intern/rna_ui.cc

@@ -1282,6 +1282,138 @@ static void rna_Menu_bl_description_set(PointerRNA *ptr, const char *value)
 
 /* UILayout */
 
+/* File Drop */
+
+static bool file_drop_poll(const bContext *C, FileDropType *file_drop_type, const char *extension)
+{
+  extern FunctionRNA rna_FileDrop_poll_extension_func;
+
+  PointerRNA ptr;
+  RNA_pointer_create(nullptr, file_drop_type->rna_ext.srna, nullptr, &ptr); /* dummy */
+  /* RNA_struct_find_function(&ptr, "poll"); */
+  FunctionRNA *func = &rna_FileDrop_poll_extension_func;
+
+  ParameterList list;
+  RNA_parameter_list_create(&list, &ptr, func);
+  RNA_parameter_set_lookup(&list, "context", &C);
+  RNA_parameter_set_lookup(&list, "extension", &extension);
+  file_drop_type->rna_ext.call((bContext *)C, &ptr, func, &list);
+
+  void *ret;
+  RNA_parameter_get_lookup(&list, "visible", &ret);
+  /* Get the value before freeing. */
+  const bool is_visible = *(bool *)ret;
+
+  RNA_parameter_list_free(&list);
+
+  return is_visible;
+}
+
+static bool rna_FileDrop_unregister(Main * /*bmain*/, StructRNA *type)
+{
+  FileDropType *file_drop_type = static_cast<FileDropType *>(RNA_struct_blender_type_get(type));
+
+  if (!file_drop_type) {
+    return false;
+  }
+
+  SpaceType *space_type = BKE_spacetype_from_id(file_drop_type->space_type);
+  if (!space_type) {
+    return false;
+  }
+
+  RNA_struct_free_extension(type, &file_drop_type->rna_ext);
+  RNA_struct_free(&BLENDER_RNA, type);
+
+  BLI_freelinkN(&space_type->file_drop_types, file_drop_type);
+
+  /* update while blender is running */
+  WM_main_add_notifier(NC_WINDOW, nullptr);
+
+  return true;
+}
+
+static StructRNA *rna_FileDrop_register(Main *bmain,
+                                        ReportList *reports,
+                                        void *data,
+                                        const char *identifier,
+                                        StructValidateFunc validate,
+                                        StructCallbackFunc call,
+                                        StructFreeFunc free)
+{
+  FileDropType dummy_file_drop_type = {};
+  FileDrop dummy_file_drop = {};
+  PointerRNA dummy_file_drop_ptr;
+  dummy_file_drop.type = &dummy_file_drop_type;
+  /* setup dummy file drop type to store static properties in */
+  RNA_pointer_create(nullptr, &RNA_FileDrop, &dummy_file_drop, &dummy_file_drop_ptr);
+
+  bool have_function[1];
+
+  /* validate the python class */
+  if (validate(&dummy_file_drop_ptr, data, have_function) != 0) {
+    return nullptr;
+  }
+
+  if (strlen(identifier) >= sizeof(dummy_file_drop_type.idname)) {
+    BKE_reportf(reports,
+                RPT_ERROR,
+                "Registering file drop class: '%s' is too long, maximum length is %d",
+                identifier,
+                (int)sizeof(dummy_file_drop_type.idname));
+    return nullptr;
+  }
+
+  SpaceType *space_type = BKE_spacetype_from_id(dummy_file_drop_type.space_type);
+  if (!space_type) {
+    BLI_assert_unreachable();
+    return nullptr;
+  }
+
+  /* Check if we have registered this file drop type before, and remove it. */
+  LISTBASE_FOREACH (FileDropType *, iter_file_drop_type, &space_type->file_drop_types) {
+    if (STREQ(iter_file_drop_type->idname, dummy_file_drop_type.idname)) {
+      if (iter_file_drop_type->rna_ext.srna) {
+        rna_FileDrop_unregister(bmain, iter_file_drop_type->rna_ext.srna);
+      }
+      break;
+    }
+  }
+  if (!RNA_struct_available_or_report(reports, dummy_file_drop_type.idname)) {
+    return nullptr;
+  }
+  if (!RNA_struct_bl_idname_ok_or_report(reports, dummy_file_drop_type.idname, "_FDT_")) {
+    return nullptr;
+  }
+
+  /* Create the new file drop type. */
+  FileDropType *file_drop_type = MEM_cnew<FileDropType>(__func__);
+  memcpy(file_drop_type, &dummy_file_drop_type, sizeof(*file_drop_type));
+
+  file_drop_type->rna_ext.srna = RNA_def_struct_ptr(
+      &BLENDER_RNA, file_drop_type->idname, &RNA_FileDrop);
+  file_drop_type->rna_ext.data = data;
+  file_drop_type->rna_ext.call = call;
+  file_drop_type->rna_ext.free = free;
+  RNA_struct_blender_type_set(file_drop_type->rna_ext.srna, file_drop_type);
+
+  file_drop_type->poll_extension = have_function[0] ? file_drop_poll : nullptr;
+
+  BLI_addtail(&space_type->file_drop_types, file_drop_type);
+
+  /* update while blender is running */
+  WM_main_add_notifier(NC_WINDOW, nullptr);
+
+  return file_drop_type->rna_ext.srna;
+}
+
+static StructRNA *rna_FileDrop_refine(PointerRNA *file_drop_ptr)
+{
+  FileDrop *file_drop = (FileDrop *)file_drop_ptr->data;
+  return (file_drop && file_drop->type->rna_ext.srna) ? file_drop->type->rna_ext.srna :
+                                                        &RNA_FileDrop;
+}
+
 static bool rna_UILayout_active_get(PointerRNA *ptr)
 {
   return uiLayoutGetActive(static_cast<uiLayout *>(ptr->data));
@@ -2073,6 +2205,61 @@ static void rna_def_menu(BlenderRNA *brna)
   RNA_define_verify_sdna(true);
 }
 
+static void rna_def_file_drop(BlenderRNA *brna)
+{
+  StructRNA *srna;
+  PropertyRNA *prop;
+
+  srna = RNA_def_struct(brna, "FileDrop", nullptr);
+  RNA_def_struct_ui_text(srna, "File Drop Type", "File drop polling function class");
+  RNA_def_struct_sdna(srna, "FileDrop");
+  RNA_def_struct_refine_func(srna, "rna_FileDrop_refine");
+  RNA_def_struct_register_funcs(srna, "rna_FileDrop_register", "rna_FileDrop_unregister", nullptr);
+  RNA_def_struct_translation_context(srna, BLT_I18NCONTEXT_DEFAULT_BPYRNA);
+  RNA_def_struct_flag(srna, STRUCT_PUBLIC_NAMESPACE_INHERIT);
+  /* registration */
+  RNA_define_verify_sdna(false); /* not in sdna */
+  prop = RNA_def_property(srna, "bl_idname", PROP_STRING, PROP_NONE);
+  RNA_def_property_string_sdna(prop, nullptr, "type->idname");
+  RNA_def_property_flag(prop, PROP_REGISTER);
+  RNA_def_property_ui_text(prop,
+                           "ID Name",
+                           "If this is set, the asset gets a custom ID, otherwise it takes the "
+                           "name of the class used to define the menu (for example, if the "
+                           "class name is \"OBJECT_FDT_hello\", and bl_idname is not set by the "
+                           "script, then bl_idname = \"OBJECT_FDT_hello\")");
+
+  prop = RNA_def_property(srna, "bl_space_type", PROP_ENUM, PROP_NONE);
+  RNA_def_property_enum_sdna(prop, nullptr, "type->space_type");
+  RNA_def_property_enum_items(prop, rna_enum_space_type_items);
+  RNA_def_property_flag(prop, PROP_REGISTER);
+  RNA_def_property_ui_text(
+      prop, "Space Type", "The space type where file dropped cin be used by the operator");
+
+  prop = RNA_def_property(srna, "bl_operator", PROP_STRING, PROP_NONE);
+  RNA_def_property_string_sdna(prop, nullptr, "type->op_name");
+  RNA_def_property_flag(prop, PROP_REGISTER);
+  RNA_def_property_ui_text(
+      prop, "Operator", "Operator to call if the poll_extension is successful");
+
+  PropertyRNA *parm;
+  FunctionRNA *func;
+
+  func = RNA_def_function(srna, "poll_extension", nullptr);
+  RNA_def_function_ui_description(
+      func, "If this method returns a non-null output, the file importer will be used");
+  RNA_def_function_flag(func, FUNC_NO_SELF | FUNC_REGISTER_OPTIONAL);
+  RNA_def_function_return(func, RNA_def_boolean(func, "visible", true, "", ""));
+  parm = RNA_def_pointer(func, "context", "Context", "", "");
+  RNA_def_parameter_flags(parm, PropertyFlag(0), PARM_REQUIRED);
+
+  parm = RNA_def_string(
+      func, "extension", nullptr, 256, "extension", "Extension to test for dropped file");
+  RNA_def_parameter_flags(parm, PropertyFlag(0), PARM_REQUIRED);
+
+  RNA_define_verify_sdna(true);
+}
+
 static void rna_def_asset_shelf(BlenderRNA *brna)
 {
   StructRNA *srna;
@@ -2182,6 +2369,7 @@ void RNA_def_ui(BlenderRNA *brna)
   rna_def_header(brna);
   rna_def_menu(brna);
   rna_def_asset_shelf(brna);
+  rna_def_file_drop(brna);
 }
 
 #endif /* RNA_RUNTIME */

source/blender/windowmanager/WM_api.hh

@@ -1405,13 +1405,13 @@ const ListBase *WM_drag_asset_list_get(const wmDrag *drag);
 
 const char *WM_drag_get_item_name(wmDrag *drag);
 
-/* Path drag and drop. */
+/* Paths drag and drop. */
 /**
- * \param path: The path to drag. Value will be copied into the drag data so the passed string may
- *              be destructed.
+ * \param paths: The paths to drag. Values will be copied into the drag data so the passed strings
+ * may be destructed. Only paths that share the same extension of the first file will be copied.
  */
-wmDragPath *WM_drag_create_path_data(const char *path);
-const char *WM_drag_get_path(const wmDrag *drag);
+wmDragPath *WM_drag_create_path_data(blender::Span<const char *> paths);
+const blender::Span<std::string> WM_drag_get_paths(const wmDrag *drag);
 /**
  * Note that even though the enum return type uses bit-flags, this should never have multiple
  * type-bits set, so `ELEM()` like comparison is possible.

source/blender/windowmanager/WM_types.hh

@@ -108,6 +108,7 @@ struct wmWindowManager;
 
 #include "BLI_compiler_attrs.h"
 #include "BLI_utildefines.h"
+#include "BLI_vector.hh"
 #include "DNA_listBase.h"
 #include "DNA_uuid_types.h"
 #include "DNA_vec_types.h"
@@ -1129,10 +1130,15 @@ struct wmDragAssetListItem {
 };
 
 struct wmDragPath {
-  char *path;
+  const blender::Vector<std::string> paths;
   /* Note that even though the enum type uses bit-flags, this should never have multiple type-bits
    * set, so `ELEM()` like comparison is possible. */
-  int file_type; /* eFileSel_File_Types */
+  const int file_type; /* eFileSel_File_Types */
+  const std::string tooltip;
+  wmDragPath(const blender::Vector<std::string> &paths, const std::string &tooltip, int file_type)
+      : paths(std::move(paths)), file_type(file_type), tooltip(tooltip)
+  {
+  }
 };
 
 struct wmDragGreasePencilLayer {

source/blender/windowmanager/intern/wm_dragdrop.cc

@@ -768,29 +768,47 @@ const ListBase *WM_drag_asset_list_get(const wmDrag *drag)
   return &drag->asset_items;
 }
 
-wmDragPath *WM_drag_create_path_data(const char *path)
+wmDragPath *WM_drag_create_path_data(blender::Span<const char *> paths)
 {
-  wmDragPath *path_data = MEM_new<wmDragPath>("wmDragPath");
-  path_data->path = BLI_strdup(path);
-  path_data->file_type = ED_path_extension_type(path);
+  const char *extension = BLI_path_extension(paths[0]);
+  blender::Vector<std::string> filtered_paths;
+  for (auto path : paths) {
+    const char *test_ext = BLI_path_extension(path);
+    if (extension == test_ext || (extension && test_ext && STREQ(extension, test_ext))) {
+      filtered_paths.append(path);
+    }
+  }
+  const char *tooltip = paths[0];
+  char tooltip_buffer[256];
+  if (filtered_paths.size() > 1) {
+    BLI_snprintf(tooltip_buffer,
+                 ARRAY_SIZE(tooltip_buffer),
+                 TIP_("Dragging %d %s files."),
+                 filtered_paths.size(),
+                 extension ? extension : TIP_("Folder"));
+    tooltip = tooltip_buffer;
+  }
+
+  wmDragPath *path_data = MEM_new<wmDragPath>(
+      "wmDragPath", filtered_paths, tooltip, ED_path_extension_type(paths[0]));
+
   return path_data;
 }
 
 static void wm_drag_free_path_data(wmDragPath **path_data)
 {
-  MEM_freeN((*path_data)->path);
   MEM_delete(*path_data);
   *path_data = nullptr;
 }
 
-const char *WM_drag_get_path(const wmDrag *drag)
+const blender::Span<std::string> WM_drag_get_paths(const wmDrag *drag)
 {
   if (drag->type != WM_DRAG_PATH) {
-    return nullptr;
+    return blender::Span<std::string>();
   }
 
   const wmDragPath *path_data = static_cast<const wmDragPath *>(drag->poin);
-  return path_data->path;
+  return path_data->paths.as_span();
 }
 
 int WM_drag_get_path_file_type(const wmDrag *drag)
@@ -854,7 +872,7 @@ const char *WM_drag_get_item_name(wmDrag *drag)
     }
     case WM_DRAG_PATH: {
       const wmDragPath *path_drag_data = static_cast<const wmDragPath *>(drag->poin);
-      return path_drag_data->path;
+      return path_drag_data->tooltip.c_str();
     }
     case WM_DRAG_NAME:
       return static_cast<const char *>(drag->poin);

source/blender/windowmanager/intern/wm_window.cc

@@ -1511,11 +1511,12 @@ static bool ghost_event_proc(GHOST_EventHandle evt, GHOST_TUserDataPtr C_void_pt
         if (ddd->dataType == GHOST_kDragnDropTypeFilenames) {
           GHOST_TStringArray *stra = static_cast<GHOST_TStringArray *>(ddd->data);
 
-          for (int a = 0; a < stra->count; a++) {
-            printf("drop file %s\n", stra->strings[a]);
+          if (stra->count) {
+            printf("drop file %s\n", stra->strings[0]);
             /* try to get icon type from extension */
-            int icon = ED_file_extension_icon((char *)stra->strings[a]);
-            wmDragPath *path_data = WM_drag_create_path_data((char *)stra->strings[a]);
+            int icon = ED_file_extension_icon((char *)stra->strings[0]);
+            wmDragPath *path_data = WM_drag_create_path_data(
+                blender::Span((char **)stra->strings, stra->count));
             WM_event_start_drag(C, icon, WM_DRAG_PATH, path_data, 0.0, WM_DRAG_NOP);
             /* Void pointer should point to string, it makes a copy. */
             break; /* only one drop element supported now */