diff --git a/source/blender/blenkernel/BKE_screen.hh b/source/blender/blenkernel/BKE_screen.hh
index 49b50238d9f..edb3b8b97ed 100644
--- a/source/blender/blenkernel/BKE_screen.hh
+++ b/source/blender/blenkernel/BKE_screen.hh
@@ -198,6 +198,14 @@ struct RegionPollParams {
   const bContext *context;
 };
 
+/* #ARegionType::lock */
+enum ARegionDrawLockFlags {
+  REGION_DRAW_LOCK_NONE = 0,
+  REGION_DRAW_LOCK_RENDER = (1 << 0),
+  REGION_DRAW_LOCK_BAKING = (1 << 1),
+  REGION_DRAW_LOCK_ALL = (REGION_DRAW_LOCK_RENDER | REGION_DRAW_LOCK_BAKING)
+};
+
 struct ARegionType {
   ARegionType *next, *prev;
   /** Unique identifier within this space, defines `RGN_TYPE_xxxx`. */
@@ -288,7 +296,8 @@ struct ARegionType {
   int keymapflag;
   /**
    * Return without drawing.
-   * lock is set by region definition, and copied to do_lock by render. can become flag.
+   * lock is set by region definition, and copied to do_lock by render.
+   * Set as bitflag value in #ARegionDrawLockFlags.
    */
   short do_lock, lock;
   /** Don't handle gizmos events behind #uiBlock's with #UI_BLOCK_CLIP_EVENTS flag set. */
@@ -695,10 +704,11 @@ void BKE_spacedata_copylist(ListBase *lb_dst, ListBase *lb_src);
 /**
  * Facility to set locks for drawing to survive (render) threads accessing drawing data.
  *
- * \note Lock can become bit-flag too.
  * \note Should be replaced in future by better local data handling for threads.
+ * \note Effect of multiple calls to this function is not accumulative. The locking flags
+ * will be set to by the last call.
  */
-void BKE_spacedata_draw_locks(bool set);
+void BKE_spacedata_draw_locks(ARegionDrawLockFlags lock_flags);
 
 /**
  * Version of #BKE_area_find_region_type that also works if \a slink
diff --git a/source/blender/blenkernel/intern/screen.cc b/source/blender/blenkernel/intern/screen.cc
index f9170612a7d..b245f319791 100644
--- a/source/blender/blenkernel/intern/screen.cc
+++ b/source/blender/blenkernel/intern/screen.cc
@@ -418,15 +418,15 @@ void BKE_spacedata_copylist(ListBase *lb_dst, ListBase *lb_src)
   }
 }
 
-void BKE_spacedata_draw_locks(bool set)
+void BKE_spacedata_draw_locks(ARegionDrawLockFlags lock_flags)
 {
   for (std::unique_ptr<SpaceType> &st : get_space_types()) {
     LISTBASE_FOREACH (ARegionType *, art, &st->regiontypes) {
-      if (set) {
-        art->do_lock = art->lock;
+      if (lock_flags != 0) {
+        art->do_lock = (art->lock & lock_flags);
       }
       else {
-        art->do_lock = false;
+        art->do_lock = 0;
       }
     }
   }
diff --git a/source/blender/editors/grease_pencil/intern/grease_pencil_lineart.cc b/source/blender/editors/grease_pencil/intern/grease_pencil_lineart.cc
index 2519ce51b46..5ac74f51c92 100644
--- a/source/blender/editors/grease_pencil/intern/grease_pencil_lineart.cc
+++ b/source/blender/editors/grease_pencil/intern/grease_pencil_lineart.cc
@@ -296,7 +296,7 @@ static void lineart_bake_startjob(void *customdata, wmJobWorkerStatus *worker_st
 
   guard_modifiers(*bj);
 
-  BKE_spacedata_draw_locks(true);
+  BKE_spacedata_draw_locks(REGION_DRAW_LOCK_BAKING);
 
   for (int frame = bj->frame_begin; frame <= bj->frame_end; frame += bj->frame_increment) {
 
@@ -334,7 +334,6 @@ static void lineart_bake_endjob(void *customdata)
 {
   LineartBakeJob *bj = static_cast<LineartBakeJob *>(customdata);
 
-  BKE_spacedata_draw_locks(false);
   WM_set_locked_interface(CTX_wm_manager(bj->C), false);
 
   WM_main_add_notifier(NC_SCENE | ND_FRAME, bj->scene);
@@ -401,7 +400,7 @@ static wmOperatorStatus lineart_bake_common(bContext *C,
     WM_jobs_timer(wm_job, 0.1, NC_GPENCIL | ND_DATA | NA_EDITED, NC_GPENCIL | ND_DATA | NA_EDITED);
     WM_jobs_callbacks(wm_job, lineart_bake_startjob, nullptr, nullptr, lineart_bake_endjob);
 
-    WM_set_locked_interface(CTX_wm_manager(C), true);
+    WM_set_locked_interface_with_flags(CTX_wm_manager(C), REGION_DRAW_LOCK_BAKING);
 
     WM_jobs_start(CTX_wm_manager(C), wm_job);
 
diff --git a/source/blender/editors/interface/regions/interface_region_hud.cc b/source/blender/editors/interface/regions/interface_region_hud.cc
index 2e1274c2cdd..d94c128dc73 100644
--- a/source/blender/editors/interface/regions/interface_region_hud.cc
+++ b/source/blender/editors/interface/regions/interface_region_hud.cc
@@ -309,7 +309,7 @@ ARegionType *ED_area_type_hud(int space_type)
 
   hud_panels_register(art, space_type, art->regionid);
 
-  art->lock = 1; /* can become flag, see BKE_spacedata_draw_locks */
+  art->lock = REGION_DRAW_LOCK_ALL;
   return art;
 }
 
diff --git a/source/blender/editors/interface/templates/interface_template_node_inputs.cc b/source/blender/editors/interface/templates/interface_template_node_inputs.cc
index 36a2ac5e219..9ae1e34caa9 100644
--- a/source/blender/editors/interface/templates/interface_template_node_inputs.cc
+++ b/source/blender/editors/interface/templates/interface_template_node_inputs.cc
@@ -160,8 +160,20 @@ void uiTemplateNodeInputs(uiLayout *layout, bContext *C, PointerRNA *ptr)
         blender::ui::nodes::draw_node_inputs_recursive(C, layout, node, ptr, *panel_decl);
       }
       else if (const auto *socket_decl = dynamic_cast<const SocketDeclaration *>(item_decl)) {
-        if (socket_decl->in_out == SOCK_IN) {
-          blender::ui::nodes::draw_node_input(C, layout, ptr, node.socket_by_decl(*socket_decl));
+        bNodeSocket &socket = node.socket_by_decl(*socket_decl);
+        if (socket_decl->custom_draw_fn) {
+          CustomSocketDrawParams params{
+              *C,
+              *layout,
+              tree,
+              node,
+              socket,
+              *ptr,
+              RNA_pointer_create_discrete(ptr->owner_id, &RNA_NodeSocket, &socket)};
+          (*socket_decl->custom_draw_fn)(params);
+        }
+        else if (socket_decl->in_out == SOCK_IN) {
+          blender::ui::nodes::draw_node_input(C, layout, ptr, socket);
         }
       }
       else if (const auto *layout_decl = dynamic_cast<const LayoutDeclaration *>(item_decl)) {
diff --git a/source/blender/editors/mesh/meshtools.cc b/source/blender/editors/mesh/meshtools.cc
index bc0cc6333c1..b7dcca869d4 100644
--- a/source/blender/editors/mesh/meshtools.cc
+++ b/source/blender/editors/mesh/meshtools.cc
@@ -738,7 +738,7 @@ wmOperatorStatus ED_mesh_shapes_join_objects_exec(bContext *C,
   };
 
   auto topology_count_matches = [](const Mesh &a, const Mesh &b) {
-    return a.verts_num == b.verts_num && a.edges_num == b.edges_num && a.faces_num == b.faces_num;
+    return a.verts_num == b.verts_num;
   };
 
   bool found_object = false;
@@ -778,9 +778,7 @@ wmOperatorStatus ED_mesh_shapes_join_objects_exec(bContext *C,
   }
 
   if (found_non_equal_count) {
-    BKE_report(reports,
-               RPT_WARNING,
-               "Selected meshes must have equal numbers of vertices, edges, and faces");
+    BKE_report(reports, RPT_WARNING, "Selected meshes must have equal numbers of vertices");
     return OPERATOR_CANCELLED;
   }
 
@@ -799,10 +797,12 @@ wmOperatorStatus ED_mesh_shapes_join_objects_exec(bContext *C,
   }
 
   int keys_changed = 0;
+  bool any_keys_added = false;
   for (const ObjectInfo &info : compatible_objects) {
     if (ensure_keys_exist) {
       KeyBlock *kb = BKE_keyblock_add(active_mesh.key, info.name.c_str());
       BKE_keyblock_convert_from_mesh(&info.mesh, active_mesh.key, kb);
+      any_keys_added = true;
     }
     else if (KeyBlock *kb = BKE_keyblock_find_name(active_mesh.key, info.name.c_str())) {
       keys_changed++;
@@ -821,6 +821,11 @@ wmOperatorStatus ED_mesh_shapes_join_objects_exec(bContext *C,
   DEG_id_tag_update(&active_mesh.id, ID_RECALC_GEOMETRY);
   WM_main_add_notifier(NC_GEOM | ND_DATA, &active_mesh.id);
 
+  if (any_keys_added && bmain) {
+    /* Adding a new shape key should trigger a rebuild of relationships. */
+    DEG_relations_tag_update(bmain);
+  }
+
   return OPERATOR_FINISHED;
 }
 
diff --git a/source/blender/editors/physics/dynamicpaint_ops.cc b/source/blender/editors/physics/dynamicpaint_ops.cc
index 397cbcd6788..84a4af22409 100644
--- a/source/blender/editors/physics/dynamicpaint_ops.cc
+++ b/source/blender/editors/physics/dynamicpaint_ops.cc
@@ -316,7 +316,6 @@ static void dpaint_bake_endjob(void *customdata)
   dynamicPaint_freeSurfaceData(job->surface);
 
   G.is_rendering = false;
-  BKE_spacedata_draw_locks(false);
 
   WM_set_locked_interface(static_cast<wmWindowManager *>(G_MAIN->wm.first), false);
 
@@ -445,7 +444,7 @@ static void dpaint_bake_startjob(void *customdata, wmJobWorkerStatus *worker_sta
    * scene frame in separate threads
    */
   G.is_rendering = true;
-  BKE_spacedata_draw_locks(true);
+  BKE_spacedata_draw_locks(REGION_DRAW_LOCK_BAKING);
 
   dynamicPaint_bakeImageSequence(job);
 
@@ -506,7 +505,7 @@ static wmOperatorStatus dynamicpaint_bake_exec(bContext *C, wmOperator *op)
   WM_jobs_timer(wm_job, 0.1, NC_OBJECT | ND_MODIFIER, NC_OBJECT | ND_MODIFIER);
   WM_jobs_callbacks(wm_job, dpaint_bake_startjob, nullptr, nullptr, dpaint_bake_endjob);
 
-  WM_set_locked_interface(CTX_wm_manager(C), true);
+  WM_set_locked_interface_with_flags(CTX_wm_manager(C), REGION_DRAW_LOCK_BAKING);
 
   /* Bake Dynamic Paint */
   WM_jobs_start(CTX_wm_manager(C), wm_job);
diff --git a/source/blender/editors/physics/physics_fluid.cc b/source/blender/editors/physics/physics_fluid.cc
index 47bb5870052..2040e3a5a03 100644
--- a/source/blender/editors/physics/physics_fluid.cc
+++ b/source/blender/editors/physics/physics_fluid.cc
@@ -329,7 +329,6 @@ static void fluid_bake_endjob(void *customdata)
   DEG_id_tag_update(&job->ob->id, ID_RECALC_GEOMETRY);
 
   G.is_rendering = false;
-  BKE_spacedata_draw_locks(false);
   WM_set_locked_interface(static_cast<wmWindowManager *>(G_MAIN->wm.first), false);
 
   /* Bake was successful:
@@ -367,7 +366,7 @@ static void fluid_bake_startjob(void *customdata, wmJobWorkerStatus *worker_stat
 
   G.is_break = false;
   G.is_rendering = true;
-  BKE_spacedata_draw_locks(true);
+  BKE_spacedata_draw_locks(REGION_DRAW_LOCK_BAKING);
 
   if (fluid_is_bake_noise(job) || fluid_is_bake_all(job)) {
     BLI_path_join(temp_dir, sizeof(temp_dir), fds->cache_directory, FLUID_DOMAIN_DIR_NOISE);
@@ -436,7 +435,6 @@ static void fluid_free_endjob(void *customdata)
   FluidDomainSettings *fds = job->fmd->domain;
 
   G.is_rendering = false;
-  BKE_spacedata_draw_locks(false);
   WM_set_locked_interface(static_cast<wmWindowManager *>(G_MAIN->wm.first), false);
 
   /* Reflect the now empty cache in the viewport too. */
@@ -474,7 +472,7 @@ static void fluid_free_startjob(void *customdata, wmJobWorkerStatus *worker_stat
 
   G.is_break = false;
   G.is_rendering = true;
-  BKE_spacedata_draw_locks(true);
+  BKE_spacedata_draw_locks(REGION_DRAW_LOCK_BAKING);
 
   int cache_map = 0;
 
@@ -571,7 +569,7 @@ static wmOperatorStatus fluid_bake_invoke(bContext *C, wmOperator *op, const wmE
   WM_jobs_timer(wm_job, 0.01, NC_OBJECT | ND_MODIFIER, NC_OBJECT | ND_MODIFIER);
   WM_jobs_callbacks(wm_job, fluid_bake_startjob, nullptr, nullptr, fluid_bake_endjob);
 
-  WM_set_locked_interface(CTX_wm_manager(C), true);
+  WM_set_locked_interface_with_flags(CTX_wm_manager(C), REGION_DRAW_LOCK_BAKING);
 
   WM_jobs_start(CTX_wm_manager(C), wm_job);
   WM_event_add_modal_handler(C, op);
@@ -653,7 +651,7 @@ static wmOperatorStatus fluid_free_exec(bContext *C, wmOperator *op)
   WM_jobs_timer(wm_job, 0.01, NC_OBJECT | ND_MODIFIER, NC_OBJECT | ND_MODIFIER);
   WM_jobs_callbacks(wm_job, fluid_free_startjob, nullptr, nullptr, fluid_free_endjob);
 
-  WM_set_locked_interface(CTX_wm_manager(C), true);
+  WM_set_locked_interface_with_flags(CTX_wm_manager(C), REGION_DRAW_LOCK_BAKING);
 
   /*  Free Fluid Geometry */
   WM_jobs_start(CTX_wm_manager(C), wm_job);
diff --git a/source/blender/editors/render/render_internal.cc b/source/blender/editors/render/render_internal.cc
index f0d193ad6ce..81f1b37bfef 100644
--- a/source/blender/editors/render/render_internal.cc
+++ b/source/blender/editors/render/render_internal.cc
@@ -881,7 +881,7 @@ static void render_drawlock(void *rjv, bool lock)
 
   /* If interface is locked, renderer callback shall do nothing. */
   if (!rj->interface_locked) {
-    BKE_spacedata_draw_locks(lock);
+    BKE_spacedata_draw_locks(lock ? REGION_DRAW_LOCK_RENDER : REGION_DRAW_LOCK_NONE);
   }
 }
 
@@ -1061,7 +1061,7 @@ static wmOperatorStatus screen_render_invoke(bContext *C, wmOperator *op, const
 
   /* Lock the user interface depending on render settings. */
   if (scene->r.use_lock_interface) {
-    WM_set_locked_interface(CTX_wm_manager(C), true);
+    WM_set_locked_interface_with_flags(CTX_wm_manager(C), REGION_DRAW_LOCK_RENDER);
 
     /* Set flag interface need to be unlocked.
      *
diff --git a/source/blender/editors/space_buttons/space_buttons.cc b/source/blender/editors/space_buttons/space_buttons.cc
index 75ba393eae3..cdc933717a1 100644
--- a/source/blender/editors/space_buttons/space_buttons.cc
+++ b/source/blender/editors/space_buttons/space_buttons.cc
@@ -1100,7 +1100,7 @@ void ED_spacetype_buttons()
   art->draw = ED_region_panels_draw;
   art->listener = buttons_main_region_listener;
   art->keymapflag = ED_KEYMAP_UI | ED_KEYMAP_FRAMES;
-  art->lock = true;
+  art->lock = REGION_DRAW_LOCK_ALL;
   buttons_context_register(art);
   BLI_addhead(&st->regiontypes, art);
 
diff --git a/source/blender/editors/space_image/space_image.cc b/source/blender/editors/space_image/space_image.cc
index 49e3aa06e55..e9f7e464f81 100644
--- a/source/blender/editors/space_image/space_image.cc
+++ b/source/blender/editors/space_image/space_image.cc
@@ -1239,7 +1239,7 @@ void ED_spacetype_image()
   art->init = image_main_region_init;
   art->draw = image_main_region_draw;
   art->listener = image_main_region_listener;
-  art->lock = 1; /* can become flag, see BKE_spacedata_draw_locks */
+  art->lock = REGION_DRAW_LOCK_BAKING;
   BLI_addhead(&st->regiontypes, art);
 
   /* regions: list-view/buttons/scopes */
diff --git a/source/blender/editors/space_node/node_draw.cc b/source/blender/editors/space_node/node_draw.cc
index 460095db9f8..4e53e71842b 100644
--- a/source/blender/editors/space_node/node_draw.cc
+++ b/source/blender/editors/space_node/node_draw.cc
@@ -2790,7 +2790,9 @@ static void node_add_error_message_button(const TreeDrawContext &tree_draw_ctx,
                             0,
                             nullptr);
   UI_but_func_quick_tooltip_set(
-      but, [warnings](const uiBut * /*but*/) { return node_errors_tooltip_fn(warnings); });
+      but, [warnings = Array<geo_log::NodeWarning>(warnings)](const uiBut * /*but*/) {
+        return node_errors_tooltip_fn(warnings);
+      });
   UI_block_emboss_set(&block, blender::ui::EmbossType::Emboss);
 }
 
diff --git a/source/blender/editors/space_node/space_node.cc b/source/blender/editors/space_node/space_node.cc
index 655434a57ef..b04f52db946 100644
--- a/source/blender/editors/space_node/space_node.cc
+++ b/source/blender/editors/space_node/space_node.cc
@@ -2264,7 +2264,7 @@ void ED_spacetype_node()
   art->cursor = node_cursor;
   art->event_cursor = true;
   art->clip_gizmo_events_by_ui = true;
-  art->lock = 1;
+  art->lock = REGION_DRAW_LOCK_ALL;
 
   BLI_addhead(&st->regiontypes, art);
 
diff --git a/source/blender/editors/space_spreadsheet/space_spreadsheet.cc b/source/blender/editors/space_spreadsheet/space_spreadsheet.cc
index 38fddf1c0b0..85630d3ca57 100644
--- a/source/blender/editors/space_spreadsheet/space_spreadsheet.cc
+++ b/source/blender/editors/space_spreadsheet/space_spreadsheet.cc
@@ -793,7 +793,7 @@ void register_spacetype()
   art = MEM_callocN<ARegionType>("spacetype spreadsheet region");
   art->regionid = RGN_TYPE_WINDOW;
   art->keymapflag = ED_KEYMAP_UI | ED_KEYMAP_VIEW2D | ED_KEYMAP_FRAMES;
-  art->lock = 1;
+  art->lock = REGION_DRAW_LOCK_ALL;
 
   art->init = spreadsheet_main_region_init;
   art->draw = spreadsheet_main_region_draw;
@@ -808,7 +808,7 @@ void register_spacetype()
   art->prefsizey = HEADERY;
   art->keymapflag = 0;
   art->keymapflag = ED_KEYMAP_UI | ED_KEYMAP_VIEW2D | ED_KEYMAP_HEADER | ED_KEYMAP_FRAMES;
-  art->lock = 1;
+  art->lock = REGION_DRAW_LOCK_ALL;
 
   art->init = spreadsheet_header_region_init;
   art->draw = spreadsheet_header_region_draw;
@@ -822,7 +822,7 @@ void register_spacetype()
   art->prefsizey = HEADERY;
   art->keymapflag = 0;
   art->keymapflag = ED_KEYMAP_UI | ED_KEYMAP_VIEW2D | ED_KEYMAP_HEADER | ED_KEYMAP_FRAMES;
-  art->lock = 1;
+  art->lock = REGION_DRAW_LOCK_ALL;
 
   art->init = spreadsheet_footer_region_init;
   art->draw = spreadsheet_footer_region_draw;
@@ -835,7 +835,7 @@ void register_spacetype()
   art->regionid = RGN_TYPE_UI;
   art->prefsizex = UI_SIDEBAR_PANEL_WIDTH;
   art->keymapflag = ED_KEYMAP_UI | ED_KEYMAP_FRAMES;
-  art->lock = 1;
+  art->lock = REGION_DRAW_LOCK_ALL;
 
   art->init = spreadsheet_sidebar_init;
   art->layout = ED_region_panels_layout;
@@ -851,7 +851,7 @@ void register_spacetype()
   art->regionid = RGN_TYPE_TOOLS;
   art->prefsizex = 150 + V2D_SCROLL_WIDTH;
   art->keymapflag = ED_KEYMAP_UI | ED_KEYMAP_FRAMES;
-  art->lock = 1;
+  art->lock = REGION_DRAW_LOCK_ALL;
   art->init = ED_region_panels_init;
   art->draw = spreadsheet_dataset_region_draw;
   art->listener = spreadsheet_dataset_region_listener;
diff --git a/source/blender/editors/space_view3d/space_view3d.cc b/source/blender/editors/space_view3d/space_view3d.cc
index b6a9aa9d7e4..f4f760ff228 100644
--- a/source/blender/editors/space_view3d/space_view3d.cc
+++ b/source/blender/editors/space_view3d/space_view3d.cc
@@ -1621,7 +1621,7 @@ void ED_spacetype_view3d()
   art->listener = view3d_main_region_listener;
   art->message_subscribe = view3d_main_region_message_subscribe;
   art->cursor = view3d_main_region_cursor;
-  art->lock = 1; /* can become flag, see BKE_spacedata_draw_locks */
+  art->lock = REGION_DRAW_LOCK_ALL;
   BLI_addhead(&st->regiontypes, art);
 
   /* regions: list-view/buttons */
diff --git a/source/blender/editors/uvedit/uvedit_unwrap_ops.cc b/source/blender/editors/uvedit/uvedit_unwrap_ops.cc
index a42eb626502..9078f3063e6 100644
--- a/source/blender/editors/uvedit/uvedit_unwrap_ops.cc
+++ b/source/blender/editors/uvedit/uvedit_unwrap_ops.cc
@@ -46,6 +46,7 @@
 #include "BKE_mesh.hh"
 #include "BKE_object_types.hh"
 #include "BKE_report.hh"
+#include "BKE_screen.hh"
 #include "BKE_subdiv.hh"
 #include "BKE_subdiv_mesh.hh"
 #include "BKE_subdiv_modifier.hh"
@@ -1800,7 +1801,7 @@ static wmOperatorStatus pack_islands_exec(bContext *C, wmOperator *op)
         pid->wm, CTX_wm_window(C), scene, "Packing UVs", WM_JOB_PROGRESS, WM_JOB_TYPE_UV_PACK);
     WM_jobs_customdata_set(wm_job, pid, pack_islands_freejob);
     WM_jobs_timer(wm_job, 0.1, 0, 0);
-    WM_set_locked_interface(pid->wm, true);
+    WM_set_locked_interface_with_flags(pid->wm, REGION_DRAW_LOCK_RENDER);
     WM_jobs_callbacks(wm_job, pack_islands_startjob, nullptr, nullptr, pack_islands_endjob);
 
     WM_cursor_wait(true);
diff --git a/source/blender/windowmanager/WM_api.hh b/source/blender/windowmanager/WM_api.hh
index 183c6362c88..4695210a6f7 100644
--- a/source/blender/windowmanager/WM_api.hh
+++ b/source/blender/windowmanager/WM_api.hh
@@ -1954,8 +1954,10 @@ void WM_autosave_write(wmWindowManager *wm, Main *bmain);
 
 /**
  * Lock the interface for any communication.
+ * For #WM_set_locked_interface_with_flags, #lock_flags is #ARegionDrawLockFlags
  */
 void WM_set_locked_interface(wmWindowManager *wm, bool lock);
+void WM_set_locked_interface_with_flags(wmWindowManager *wm, short lock_flags);
 
 void WM_event_tablet_data_default_set(wmTabletData *tablet_data);
 
diff --git a/source/blender/windowmanager/intern/wm_event_system.cc b/source/blender/windowmanager/intern/wm_event_system.cc
index 83775dc079d..fc0cc954141 100644
--- a/source/blender/windowmanager/intern/wm_event_system.cc
+++ b/source/blender/windowmanager/intern/wm_event_system.cc
@@ -6456,7 +6456,7 @@ static bool wm_operator_check_locked_interface(bContext *C, wmOperatorType *ot)
   return true;
 }
 
-void WM_set_locked_interface(wmWindowManager *wm, bool lock)
+void WM_set_locked_interface_with_flags(wmWindowManager *wm, short lock_flags)
 {
   /* This will prevent events from being handled while interface is locked
    *
@@ -6465,16 +6465,14 @@ void WM_set_locked_interface(wmWindowManager *wm, bool lock)
    * wouldn't be useful anywhere outside of window manager, so let's not
    * pollute global context with such an information for now).
    */
-  wm->runtime->is_interface_locked = lock;
+  wm->runtime->is_interface_locked = (lock_flags != 0);
 
-  /* This will prevent drawing regions which uses non-thread-safe data.
-   * Currently it'll be just a 3D viewport.
-   *
-   * TODO(sergey): Make it different locked states, so different jobs
-   *               could lock different areas of blender and allow
-   *               interaction with others?
-   */
-  BKE_spacedata_draw_locks(lock);
+  BKE_spacedata_draw_locks(static_cast<ARegionDrawLockFlags>(lock_flags));
+}
+
+void WM_set_locked_interface(wmWindowManager *wm, bool lock)
+{
+  WM_set_locked_interface_with_flags(wm, lock ? REGION_DRAW_LOCK_ALL : 0);
 }
 
 /** \} */