Keymap: preference for fallback-tool with RMB select

Expose a key-map preference "Fallback Tool (RMB)",
disabled by default.

The right mouse button uses the fallback tool
(currently visible selection tool in the toolbar),
instead of always tweaking.

When any selection tool is active, right mouse always tweaks.

To enable fallback selection on RMB, set the "Right Mouse Select Action"
to "Selection Tool".

Internal changes:

- Add fall-back key-maps, separate key-maps needed for when the tool is
  run as a fall-back. This is needed so RMB-select can support fall-back
  tools, so left-mouse can be used when it's the active tool and RMB
  can be used as a fall-back action when another tool is active.
- Add options field to tools so tools without gizmos can enable the
  full-back tool keymap.
- Support multiple key-maps for keymap handlers.
- Fall-back keymaps now co-exist with the tool-keymaps.
  So both keymaps may be active at once - using different mouse buttons.
  When gizmos are in use, a highlighted gizmo prioritizes the
  tool-keymap over the fall-back keymap.

Resolves T83690.

Reviewed By: JulienKaspar

Ref D12493

16 files changed, 517 insertions, 208 deletions

diff --git a/release/scripts/modules/bpy/utils/__init__.py b/release/scripts/modules/bpy/utils/__init__.py
index afa04a18ef6..3f0248970c6 100644
--- a/release/scripts/modules/bpy/utils/__init__.py
+++ b/release/scripts/modules/bpy/utils/__init__.py
@@ -858,6 +858,7 @@ def register_tool(tool_cls, *, after=None, separator=False, group=False):
             "description": getattr(tool_cls, "bl_description", tool_cls.__doc__),
             "icon": getattr(tool_cls, "bl_icon", None),
             "cursor": getattr(tool_cls, "bl_cursor", None),
+            "options": getattr(tool_cls, "bl_options", None),
             "widget": getattr(tool_cls, "bl_widget", None),
             "widget_properties": getattr(tool_cls, "bl_widget_properties", None),
             "keymap": getattr(tool_cls, "bl_keymap", None),
diff --git a/release/scripts/presets/keyconfig/Blender.py b/release/scripts/presets/keyconfig/Blender.py
index eb66c961472..1690b03184a 100644
--- a/release/scripts/presets/keyconfig/Blender.py
+++ b/release/scripts/presets/keyconfig/Blender.py
@@ -54,6 +54,19 @@ class Prefs(bpy.types.KeyConfigPreferences):
         default='PLAY',
         update=update_fn,
     )
+    rmb_action: EnumProperty(
+        name="Right Mouse Select Action",
+        items=(
+            ('TWEAK', "Select & Tweak",
+             "Right mouse always tweaks"),
+            ('FALLBACK_TOOL', "Selection Tool",
+             "Right mouse uses the selection tool"),
+        ),
+        description=(
+            "Default action for the right mouse button"
+        ),
+        update=update_fn,
+    )
     use_alt_click_leader: BoolProperty(
         name="Alt Click Tool Prompt",
         description=(
@@ -179,6 +192,8 @@ class Prefs(bpy.types.KeyConfigPreferences):
 
         if is_select_left:
             col.row().prop(self, "gizmo_action", text="Activate Gizmo Event", expand=True)
+        else:
+            col.row().prop(self, "rmb_action", text="Right Mouse Select Action", expand=True)
 
         # Checkboxes sub-layout.
         col = layout.column()
@@ -232,6 +247,7 @@ def load():
                 kc_prefs.select_mouse == 'LEFT' and
                 kc_prefs.gizmo_action == 'DRAG'
             ),
+            use_fallback_tool=(True if (kc_prefs.select_mouse == 'LEFT') else (kc_prefs.rmb_action == 'FALLBACK_TOOL')),
             use_alt_click_leader=kc_prefs.use_alt_click_leader,
             use_pie_click_drag=kc_prefs.use_pie_click_drag,
         ),
diff --git a/release/scripts/presets/keyconfig/keymap_data/blender_default.py b/release/scripts/presets/keyconfig/keymap_data/blender_default.py
index 44b77ab2aac..6a3064fc820 100644
--- a/release/scripts/presets/keyconfig/keymap_data/blender_default.py
+++ b/release/scripts/presets/keyconfig/keymap_data/blender_default.py
@@ -46,6 +46,8 @@ class Params:
         "use_select_all_toggle",
         # Activate gizmo on drag (which support it).
         "use_gizmo_drag",
+        # Use the fallback tool instead of tweak for RMB select.
+        "use_fallback_tool",
         # Use pie menu for tab by default (swap 'Tab/Ctrl-Tab').
         "use_v3d_tab_menu",
         # Use extended pie menu for shading.
@@ -59,6 +61,15 @@ class Params:
         "v3d_tilde_action",
         # Alt-MMB axis switching 'RELATIVE' or 'ABSOLUTE' axis switching.
         "v3d_alt_mmb_drag_action",
+
+        # Convenience variables:
+        # (derived from other settings).
+        #
+        # This case needs to be checked often,
+        # convenience for: `params.use_fallback_tool if params.select_mouse == 'RIGHT' else False`.
+        "use_fallback_tool_rmb",
+        # Convenience for: `'CLICK' if params.use_fallback_tool_rmb else params.select_mouse_value`.
+        "select_mouse_value_fallback",
     )
 
     def __init__(
@@ -72,6 +83,7 @@ class Params:
             spacebar_action='TOOL',
             use_select_all_toggle=False,
             use_gizmo_drag=True,
+            use_fallback_tool=False,
             use_v3d_tab_menu=False,
             use_v3d_shade_ex_pie=False,
             use_v3d_mmb_pan=False,
@@ -96,6 +108,9 @@ class Params:
             self.context_menu_event = {"type": 'W', "value": 'PRESS'}
             self.cursor_set_event = {"type": 'LEFTMOUSE', "value": 'CLICK'}
             self.cursor_tweak_event = None
+            self.use_fallback_tool = use_fallback_tool
+            self.use_fallback_tool_rmb = use_fallback_tool
+            self.select_mouse_value_fallback = 'CLICK' if self.use_fallback_tool_rmb else self.select_mouse_value
         else:
             # Left mouse select uses Click event for selection. This is a little
             # less immediate, but is needed to distinguish between click and tweak
@@ -115,6 +130,10 @@ class Params:
 
             self.cursor_set_event = {"type": 'RIGHTMOUSE', "value": 'PRESS', "shift": True}
             self.cursor_tweak_event = {"type": 'EVT_TWEAK_R', "value": 'ANY', "shift": True}
+            self.use_fallback_tool = True
+            self.use_fallback_tool_rmb = False
+            self.select_mouse_value_fallback = self.select_mouse_value
+
 
         self.use_mouse_emulate_3_button = use_mouse_emulate_3_button
 
@@ -148,6 +167,15 @@ NUMBERS_0 = ('ZERO', 'ONE', 'TWO', 'THREE', 'FOUR', 'FIVE', 'SIX', 'SEVEN', 'EIG
 
 
 # ------------------------------------------------------------------------------
+# Generic Utilities
+
+def _fallback_id(text, fallback):
+    if fallback:
+        return text + " (fallback)"
+    return text
+
+
+# ------------------------------------------------------------------------------
 # Keymap Item Wrappers
 
 def op_menu(menu, kmi_args):
@@ -882,20 +910,25 @@ def km_uv_editor(params):
     items.extend([
         # Selection modes.
         *_template_items_uv_select_mode(params),
+        *_template_uv_select(
+            type=params.select_mouse,
+            value=('CLICK' if params.use_fallback_tool_rmb else params.select_mouse_value),
+            legacy=params.legacy,
+        ),
         ("uv.mark_seam", {"type": 'E', "value": 'PRESS', "ctrl": True}, None),
-        ("uv.select", {"type": params.select_mouse, "value": params.select_mouse_value},
-         {"properties": [("deselect_all", not params.legacy)]}),
-        ("uv.select", {"type": params.select_mouse, "value": params.select_mouse_value, "shift": True},
-         {"properties": [("extend", True)]}),
         ("uv.select_loop", {"type": params.select_mouse, "value": params.select_mouse_value, "alt": True}, None),
         ("uv.select_loop", {"type": params.select_mouse, "value": params.select_mouse_value, "shift": True, "alt": True},
          {"properties": [("extend", True)]}),
-        ("uv.select_edge_ring", {"type": params.select_mouse, "value": params.select_mouse_value, "ctrl": True, "alt": True}, None),
-        ("uv.select_edge_ring", {"type": params.select_mouse, "value": params.select_mouse_value, "ctrl": True, "shift": True, "alt": True},
+        ("uv.select_edge_ring",
+         {"type": params.select_mouse, "value": params.select_mouse_value, "ctrl": True, "alt": True}, None),
+        ("uv.select_edge_ring",
+         {"type": params.select_mouse, "value": params.select_mouse_value, "ctrl": True, "shift": True, "alt": True},
          {"properties": [("extend", True)]}),
-        ("uv.shortest_path_pick", {"type": params.select_mouse, "value": params.select_mouse_value, "ctrl": True},
+        ("uv.shortest_path_pick",
+         {"type": params.select_mouse, "value": params.select_mouse_value_fallback, "ctrl": True},
          {"properties": [("use_fill", False)]}),
-        ("uv.shortest_path_pick", {"type": params.select_mouse, "value": params.select_mouse_value, "ctrl": True, "shift": True},
+        ("uv.shortest_path_pick",
+         {"type": params.select_mouse, "value": params.select_mouse_value_fallback, "ctrl": True, "shift": True},
          {"properties": [("use_fill", True)]}),
         ("uv.select_split", {"type": 'Y', "value": 'PRESS'}, None),
         ("uv.select_box", {"type": 'B', "value": 'PRESS'},
@@ -1196,20 +1229,11 @@ def km_view3d(params):
         ("view3d.view_axis", {"type": 'NDOF_BUTTON_TOP', "value": 'PRESS', "shift": True},
          {"properties": [("type", 'TOP'), ("align_active", True)]}),
         # Selection.
-        *((
-            "view3d.select",
-            {"type": params.select_mouse, "value": params.select_mouse_value, **{m: True for m in mods}},
-            {"properties": [(c, True) for c in props]},
-        ) for props, mods in (
-            (("deselect_all",) if not params.legacy else (), ()),
-            (("toggle",), ("shift",)),
-            (("center", "object"), ("ctrl",)),
-            (("enumerate",), ("alt",)),
-            (("toggle", "center"), ("shift", "ctrl")),
-            (("center", "enumerate"), ("ctrl", "alt")),
-            (("toggle", "enumerate"), ("shift", "alt")),
-            (("toggle", "center", "enumerate"), ("shift", "ctrl", "alt")),
-        )),
+        *_template_view3d_select(
+            type=params.select_mouse,
+            value=('CLICK' if params.use_fallback_tool_rmb else params.select_mouse_value),
+            legacy=params.legacy,
+        ),
         ("view3d.select_box", {"type": 'B', "value": 'PRESS'}, None),
         ("view3d.select_lasso", {"type": params.action_tweak, "value": 'ANY', "ctrl": True},
          {"properties": [("mode", 'ADD')]}),
@@ -3203,7 +3227,7 @@ def km_grease_pencil(_params):
     return keymap
 
 
-def _grease_pencil_selection(params):
+def _grease_pencil_selection(params, use_select_mouse=True):
     return [
         # Select all
         *_template_items_select_actions(params, "gpencil.select_all"),
@@ -3225,13 +3249,12 @@ def _grease_pencil_selection(params):
          {"properties": [("mode", 'ADD')]}),
         ("gpencil.select_lasso", {"type": params.action_tweak, "value": 'ANY', "shift": True, "ctrl": True, "alt": True},
          {"properties": [("mode", 'SUB')]}),
-        ("gpencil.select", {"type": params.select_mouse, "value": params.select_mouse_value, "shift": True},
-         {"properties": [("extend", True), ("toggle", True)]}),
-        # Whole stroke select
-        ("gpencil.select", {"type": params.select_mouse, "value": params.select_mouse_value, "alt": True},
-         {"properties": [("entire_strokes", True)]}),
-        ("gpencil.select", {"type": params.select_mouse, "value": params.select_mouse_value, "shift": True, "alt": True},
-         {"properties": [("extend", True), ("entire_strokes", True)]}),
+        *_template_view3d_gpencil_select(
+            type=params.select_mouse,
+            value=params.select_mouse_value_fallback,
+            legacy=params.legacy,
+            use_select_mouse=use_select_mouse,
+        ),
         # Select linked
         ("gpencil.select_linked", {"type": 'L', "value": 'PRESS'}, None),
         ("gpencil.select_linked", {"type": 'L', "value": 'PRESS', "ctrl": True}, None),
@@ -3266,9 +3289,6 @@ def km_grease_pencil_stroke_edit_mode(params):
         # Interpolation
         ("gpencil.interpolate", {"type": 'E', "value": 'PRESS', "ctrl": True}, None),
         ("gpencil.interpolate_sequence", {"type": 'E', "value": 'PRESS', "shift": True, "ctrl": True}, None),
-        # Normal select
-        ("gpencil.select", {"type": params.select_mouse, "value": params.select_mouse_value},
-         {"properties": [("deselect_all", not params.legacy)]}),
         # Selection
         *_grease_pencil_selection(params),
         # Duplicate and move selected points
@@ -3560,7 +3580,7 @@ def km_grease_pencil_stroke_sculpt_mode(params):
 
     items.extend([
         # Selection
-        *_grease_pencil_selection(params),
+        *_grease_pencil_selection(params, use_select_mouse=False),
 
         # Brush strength
         ("wm.radial_control", {"type": 'F', "value": 'PRESS', "shift": True},
@@ -3846,7 +3866,7 @@ def km_grease_pencil_stroke_vertex_mode(params):
 
     items.extend([
         # Selection
-        *_grease_pencil_selection(params),
+        *_grease_pencil_selection(params, use_select_mouse=False),
         # Brush strength
         ("wm.radial_control", {"type": 'F', "value": 'PRESS', "shift": True},
          {"properties": [("data_path_primary", 'tool_settings.gpencil_vertex_paint.brush.gpencil_settings.pen_strength')]}),
@@ -4267,7 +4287,8 @@ def km_curve(params):
          {"properties": [("deselect", False)]}),
         ("curve.select_linked_pick", {"type": 'L', "value": 'PRESS', "shift": True},
          {"properties": [("deselect", True)]}),
-        ("curve.shortest_path_pick", {"type": params.select_mouse, "value": params.select_mouse_value, "ctrl": True}, None),
+        ("curve.shortest_path_pick",
+         {"type": params.select_mouse, "value": params.select_mouse_value_fallback, "ctrl": True}, None),
         ("curve.separate", {"type": 'P', "value": 'PRESS'}, None),
         ("curve.split", {"type": 'Y', "value": 'PRESS'}, None),
         ("curve.extrude_move", {"type": 'E', "value": 'PRESS'}, None),
@@ -4348,6 +4369,80 @@ def _template_paint_radial_control(paint, rotation=False, secondary_rotation=Fal
     return items
 
 
+def _template_view3d_select(*, type, value, legacy):
+    return [(
+        "view3d.select",
+        {"type": type, "value": value, **{m: True for m in mods}},
+        {"properties": [(c, True) for c in props]},
+    ) for props, mods in (
+        (("deselect_all",) if not legacy else (), ()),
+        (("toggle",), ("shift",)),
+        (("center", "object"), ("ctrl",)),
+        (("enumerate",), ("alt",)),
+        (("toggle", "center"), ("shift", "ctrl")),
+        (("center", "enumerate"), ("ctrl", "alt")),
+        (("toggle", "enumerate"), ("shift", "alt")),
+        (("toggle", "center", "enumerate"), ("shift", "ctrl", "alt")),
+    )]
+
+
+def _template_view3d_select_for_fallback(params, fallback):
+    if (not fallback) and params.use_fallback_tool_rmb:
+        # Needed so we have immediate select+tweak when the default select tool is active.
+        return _template_view3d_select(
+            type=params.select_mouse,
+            value=params.select_mouse_value,
+            legacy=params.legacy,
+        )
+    return []
+
+
+def _template_view3d_gpencil_select(*, type, value, legacy, use_select_mouse=True):
+    return [
+        *([] if not use_select_mouse else [
+            ("gpencil.select", {"type": type, "value": value},
+             {"properties": [("deselect_all", not legacy)]})]),
+        ("gpencil.select", {"type": type, "value": value, "shift": True},
+         {"properties": [("extend", True), ("toggle", True)]}),
+        # Whole stroke select
+        ("gpencil.select", {"type": type, "value": value, "alt": True},
+         {"properties": [("entire_strokes", True)]}),
+        ("gpencil.select", {"type": type, "value": value, "shift": True, "alt": True},
+         {"properties": [("extend", True), ("entire_strokes", True)]}),
+    ]
+
+
+def _template_view3d_gpencil_select_for_fallback(params, fallback):
+    if (not fallback) and params.use_fallback_tool_rmb:
+        # Needed so we have immediate select+tweak when the default select tool is active.
+        return _template_view3d_gpencil_select(
+            type=params.select_mouse,
+            value=params.select_mouse_value,
+            legacy=params.legacy,
+        )
+    return []
+
+
+def _template_uv_select(*, type, value, legacy):
+    return [
+        ("uv.select", {"type": type, "value": value},
+         {"properties": [("deselect_all", not legacy)]}),
+        ("uv.select", {"type": type, "value": value, "shift": True},
+         {"properties": [("extend", True)]}),
+    ]
+
+
+def _template_uv_select_for_fallback(params, fallback):
+    if (not fallback) and params.use_fallback_tool_rmb:
+        # Needed so we have immediate select+tweak when the default select tool is active.
+        return _template_uv_select(
+            type=params.select_mouse,
+            value=params.select_mouse_value,
+            legacy=params.legacy,
+        )
+    return []
+
+
 def km_image_paint(params):
     items = []
     keymap = (
@@ -4651,9 +4746,11 @@ def km_mesh(params):
         ("mesh.edgering_select", {"type": params.select_mouse, "value": params.select_mouse_value, "ctrl": True, "alt": True}, None),
         ("mesh.edgering_select", {"type": params.select_mouse, "value": params.select_mouse_value, "shift": True, "ctrl": True, "alt": True},
          {"properties": [("toggle", True)]}),
-        ("mesh.shortest_path_pick", {"type": params.select_mouse, "value": params.select_mouse_value, "ctrl": True},
+        ("mesh.shortest_path_pick",
+         {"type": params.select_mouse, "value": params.select_mouse_value_fallback, "ctrl": True},
          {"properties": [("use_fill", False)]}),
-        ("mesh.shortest_path_pick", {"type": params.select_mouse, "value": params.select_mouse_value, "shift": True, "ctrl": True},
+        ("mesh.shortest_path_pick",
+         {"type": params.select_mouse, "value": params.select_mouse_value_fallback, "shift": True, "ctrl": True},
          {"properties": [("use_fill", True)]}),
         *_template_items_select_actions(params, "mesh.select_all"),
         ("mesh.select_more", {"type": 'NUMPAD_PLUS', "value": 'PRESS', "ctrl": True, "repeat": True}, None),
@@ -4801,7 +4898,8 @@ def km_armature(params):
         ("armature.select_linked_pick", {"type": 'L', "value": 'PRESS', "shift": True},
          {"properties": [("deselect", True)]}),
         ("armature.select_linked", {"type": 'L', "value": 'PRESS', "ctrl": True}, None),
-        ("armature.shortest_path_pick", {"type": params.select_mouse, "value": params.select_mouse_value, "ctrl": True}, None),
+        ("armature.shortest_path_pick",
+         {"type": params.select_mouse, "value": params.select_mouse_value_fallback, "ctrl": True}, None),
         # Editing.
         op_menu("VIEW3D_MT_edit_armature_delete", {"type": 'X', "value": 'PRESS'}),
         op_menu("VIEW3D_MT_edit_armature_delete", {"type": 'DEL', "value": 'PRESS'}),
@@ -5825,38 +5923,60 @@ def km_image_editor_tool_uv_cursor(params):
     )
 
 
-def km_image_editor_tool_uv_select(params):
+def km_image_editor_tool_uv_select(params, *, fallback):
     return (
-        "Image Editor Tool: Uv, Tweak",
+        _fallback_id("Image Editor Tool: Uv, Tweak", fallback),
         {"space_type": 'IMAGE_EDITOR', "region_type": 'WINDOW'},
-        {"items": _template_items_tool_select(params, "uv.select", "uv.cursor_set", extend="extend")},
+        {"items": [
+            *([] if fallback else _template_items_tool_select(params, "uv.select", "uv.cursor_set", extend="extend")),
+            *([] if (not params.use_fallback_tool_rmb) else _template_uv_select(
+                type=params.select_mouse, value=params.select_mouse_value, legacy=params.legacy)),
+        ]},
     )
 
 
-def km_image_editor_tool_uv_select_box(params):
+def km_image_editor_tool_uv_select_box(params, *, fallback):
     return (
-        "Image Editor Tool: Uv, Select Box",
+        _fallback_id("Image Editor Tool: Uv, Select Box", fallback),
         {"space_type": 'IMAGE_EDITOR', "region_type": 'WINDOW'},
-        {"items": _template_items_tool_select_actions_simple("uv.select_box", type=params.tool_tweak, value='ANY')},
+        {"items": [
+            *([] if (fallback and not params.use_fallback_tool) else _template_items_tool_select_actions_simple(
+                "uv.select_box",
+                type=params.select_tweak if fallback else params.tool_tweak,
+                value='ANY')),
+            *_template_uv_select_for_fallback(params, fallback),
+        ]},
     )
 
 
-def km_image_editor_tool_uv_select_circle(params):
+def km_image_editor_tool_uv_select_circle(params, *, fallback):
     return (
-        "Image Editor Tool: Uv, Select Circle",
+        _fallback_id("Image Editor Tool: Uv, Select Circle", fallback),
         {"space_type": 'IMAGE_EDITOR', "region_type": 'WINDOW'},
-        {"items": _template_items_tool_select_actions_simple(
-            "uv.select_circle", type=params.tool_mouse, value='PRESS',
-            properties=[("wait_for_input", False)],
-        )},
+        {"items": [
+            *([] if (fallback and not params.use_fallback_tool) else _template_items_tool_select_actions_simple(
+                "uv.select_circle",
+                type=params.select_tweak if fallback else params.tool_mouse,
+                value='ANY' if fallback else 'PRESS',
+                properties=[("wait_for_input", False)])),
+            # No selection fallback since this operates on press.
+        ]},
     )
 
 
-def km_image_editor_tool_uv_select_lasso(params):
+def km_image_editor_tool_uv_select_lasso(params, *, fallback):
     return (
-        "Image Editor Tool: Uv, Select Lasso",
+        _fallback_id("Image Editor Tool: Uv, Select Lasso", fallback),
         {"space_type": 'IMAGE_EDITOR', "region_type": 'WINDOW'},
-        {"items": _template_items_tool_select_actions_simple("uv.select_lasso", type=params.tool_tweak, value='ANY')},
+
+        {"items": [
+            *([] if (fallback and not params.use_fallback_tool) else _template_items_tool_select_actions_simple(
+                "uv.select_lasso",
+                type=params.select_tweak if fallback else params.tool_tweak,
+                value='ANY')
+              ),
+            *_template_uv_select_for_fallback(params, fallback),
+        ]},
     )
 
 
@@ -5923,47 +6043,53 @@ def km_image_editor_tool_uv_scale(params):
     )
 
 
-def km_node_editor_tool_select(params):
+def km_node_editor_tool_select(params, *, fallback):
     return (
-        "Node Tool: Tweak",
+        _fallback_id("Node Tool: Tweak", fallback),
         {"space_type": 'NODE_EDITOR', "region_type": 'WINDOW'},
         {"items": [
-            ("node.select", {"type": params.select_mouse, "value": 'PRESS'},
-             {"properties": [("deselect_all", not params.legacy)]}),
+            *([] if fallback else [
+                ("node.select", {"type": params.select_mouse, "value": 'PRESS'},
+                 {"properties": [("deselect_all", not params.legacy)]}),
+            ]),
         ]},
     )
 
 
-def km_node_editor_tool_select_box(params):
+def km_node_editor_tool_select_box(params, *, fallback):
     return (
-        "Node Tool: Select Box",
+        _fallback_id("Node Tool: Select Box", fallback),
         {"space_type": 'NODE_EDITOR', "region_type": 'WINDOW'},
-        {"items": _template_items_tool_select_actions_simple(
-            "node.select_box", type=params.tool_tweak, value='ANY',
-            properties=[("tweak", True)],
-        )},
+        {"items": [
+            *([] if (fallback and not params.use_fallback_tool) else _template_items_tool_select_actions_simple(
+                "node.select_box", type=params.tool_tweak, value='ANY',
+                properties=[("tweak", True)],
+            )),
+        ]},
     )
 
 
-def km_node_editor_tool_select_lasso(params):
+def km_node_editor_tool_select_lasso(params, *, fallback):
     return (
-        "Node Tool: Select Lasso",
+        _fallback_id("Node Tool: Select Lasso", fallback),
         {"space_type": 'NODE_EDITOR', "region_type": 'WINDOW'},
-        {"items": _template_items_tool_select_actions_simple(
-            "node.select_lasso", type=params.tool_mouse, value='PRESS',
-            properties=[("tweak", True)],
-        )},
+        {"items": [
+            *([] if (fallback and not params.use_fallback_tool) else _template_items_tool_select_actions_simple(
+                "node.select_lasso", type=params.tool_mouse, value='PRESS',
+                properties=[("tweak", True)]))
+        ]},
     )
 
 
-def km_node_editor_tool_select_circle(params):
+def km_node_editor_tool_select_circle(params, *, fallback):
     return (
-        "Node Tool: Select Circle",
+        _fallback_id("Node Tool: Select Circle", fallback),
         {"space_type": 'NODE_EDITOR', "region_type": 'WINDOW'},
-        {"items": _template_items_tool_select_actions_simple(
-            "node.select_circle", type=params.tool_mouse, value='PRESS',
-            properties=[("wait_for_input", False)],
-        )},
+        {"items": [
+            *([] if (fallback and not params.use_fallback_tool) else _template_items_tool_select_actions_simple(
+                "node.select_circle", type=params.tool_mouse, value='PRESS',
+                properties=[("wait_for_input", False)])),
+        ]},
     )
 
 
@@ -5989,38 +6115,61 @@ def km_3d_view_tool_cursor(params):
     )
 
 
-def km_3d_view_tool_select(params):
+def km_3d_view_tool_select(params, *, fallback):
     return (
-        "3D View Tool: Tweak",
+        _fallback_id("3D View Tool: Tweak", fallback),
         {"space_type": 'VIEW_3D', "region_type": 'WINDOW'},
-        {"items": _template_items_tool_select(params, "view3d.select", "view3d.cursor3d", extend="toggle")},
+        {"items": [
+            *([] if fallback else _template_items_tool_select(
+                params, "view3d.select", "view3d.cursor3d", extend="toggle")),
+            *([] if (not params.use_fallback_tool_rmb) else _template_view3d_select(
+                type=params.select_mouse, value=params.select_mouse_value, legacy=params.legacy)),
+        ]},
     )
 
 
-def km_3d_view_tool_select_box(params):
+def km_3d_view_tool_select_box(params, *, fallback):
     return (
-        "3D View Tool: Select Box",
+        _fallback_id("3D View Tool: Select Box", fallback),
         {"space_type": 'VIEW_3D', "region_type": 'WINDOW'},
-        {"items": _template_items_tool_select_actions("view3d.select_box", type=params.tool_tweak, value='ANY')},
+        {"items": [
+            *([] if (fallback and not params.use_fallback_tool) else _template_items_tool_select_actions(
+                "view3d.select_box",
+                type=params.select_tweak if fallback else params.tool_tweak,
+                value='ANY')),
+            *_template_view3d_select_for_fallback(params, fallback),
+        ]},
     )
 
 
-def km_3d_view_tool_select_circle(params):
+def km_3d_view_tool_select_circle(params, *, fallback):
     return (
-        "3D View Tool: Select Circle",
+        _fallback_id("3D View Tool: Select Circle", fallback),
         {"space_type": 'VIEW_3D', "region_type": 'WINDOW'},
-        {"items": _template_items_tool_select_actions_simple(
-            "view3d.select_circle", type=params.tool_mouse, value='PRESS',
-            properties=[("wait_for_input", False)],
-        )},
+        {"items": [
+            *([] if (fallback and not params.use_fallback_tool) else _template_items_tool_select_actions_simple(
+                "view3d.select_circle",
+                # Why circle select should be used on tweak?
+                # So that RMB or Shift-RMB is still able to set an element as active.
+                type=params.select_tweak if fallback else params.tool_mouse,
+                value='ANY' if fallback else 'PRESS',
+                properties=[("wait_for_input", False)])),
+            # No selection fallback since this operates on press.
+        ]},
     )
 
 
-def km_3d_view_tool_select_lasso(params):
+def km_3d_view_tool_select_lasso(params, *, fallback):
     return (
-        "3D View Tool: Select Lasso",
+        _fallback_id("3D View Tool: Select Lasso", fallback),
         {"space_type": 'VIEW_3D', "region_type": 'WINDOW'},
-        {"items": _template_items_tool_select_actions("view3d.select_lasso", type=params.tool_tweak, value='ANY')},
+        {"items": [
+            *([] if (fallback and not params.use_fallback_tool) else _template_items_tool_select_actions(
+                "view3d.select_lasso",
+                type=params.select_tweak if fallback else params.tool_tweak,
+                value='ANY')),
+            *_template_view3d_select_for_fallback(params, fallback),
+        ]}
     )
 
 
@@ -6845,38 +6994,57 @@ def km_3d_view_tool_paint_gpencil_interpolate(params):
         ]},
     )
 
-def km_3d_view_tool_edit_gpencil_select(params):
+def km_3d_view_tool_edit_gpencil_select(params, *, fallback):
     return (
-        "3D View Tool: Edit Gpencil, Tweak",
+        _fallback_id("3D View Tool: Edit Gpencil, Tweak", fallback),
         {"space_type": 'VIEW_3D', "region_type": 'WINDOW'},
-        {"items": _template_items_tool_select(params, "gpencil.select", "view3d.cursor3d", extend="toggle")},
+        {"items": [
+            *([] if fallback else _template_items_tool_select(
+                params, "gpencil.select", "view3d.cursor3d", extend="toggle")),
+            *([] if (not params.use_fallback_tool_rmb) else _template_view3d_gpencil_select(
+                type=params.select_mouse, value=params.select_mouse_value, legacy=params.legacy)),
+        ]},
     )
 
-
-def km_3d_view_tool_edit_gpencil_select_box(params):
+def km_3d_view_tool_edit_gpencil_select_box(params, *, fallback):
     return (
-        "3D View Tool: Edit Gpencil, Select Box",
+        _fallback_id("3D View Tool: Edit Gpencil, Select Box", fallback),
         {"space_type": 'VIEW_3D', "region_type": 'WINDOW'},
-        {"items": _template_items_tool_select_actions("gpencil.select_box", type=params.tool_tweak, value='ANY')},
+        {"items": [
+            *([] if (fallback and not params.use_fallback_tool) else _template_items_tool_select_actions(
+                "gpencil.select_box", type=params.select_tweak if fallback else params.tool_tweak, value='ANY')),
+            *_template_view3d_gpencil_select_for_fallback(params, fallback),
+        ]},
     )
 
-
-def km_3d_view_tool_edit_gpencil_select_circle(params):
+def km_3d_view_tool_edit_gpencil_select_circle(params, *, fallback):
     return (
-        "3D View Tool: Edit Gpencil, Select Circle",
+        _fallback_id("3D View Tool: Edit Gpencil, Select Circle", fallback),
         {"space_type": 'VIEW_3D', "region_type": 'WINDOW'},
-        {"items": _template_items_tool_select_actions_simple(
-            "gpencil.select_circle", type=params.tool_mouse, value='PRESS',
-            properties=[("wait_for_input", False)],
-        )},
+        {"items": [
+            *([] if (fallback and not params.use_fallback_tool) else _template_items_tool_select_actions_simple(
+                "gpencil.select_circle",
+                # Why circle select should be used on tweak?
+                # So that RMB or Shift-RMB is still able to set an element as active.
+                type=params.select_tweak if fallback else params.tool_mouse,
+                value='ANY' if fallback else 'PRESS',
+                properties=[("wait_for_input", False)])),
+            # No selection fallback since this operates on press.
+        ]},
     )
 
 
-def km_3d_view_tool_edit_gpencil_select_lasso(params):
+def km_3d_view_tool_edit_gpencil_select_lasso(params, *, fallback):
     return (
-        "3D View Tool: Edit Gpencil, Select Lasso",
+        _fallback_id("3D View Tool: Edit Gpencil, Select Lasso", fallback),
         {"space_type": 'VIEW_3D', "region_type": 'WINDOW'},
-        {"items": _template_items_tool_select_actions("gpencil.select_lasso", type=params.tool_tweak, value='ANY')},
+        {"items": [
+            *([] if (fallback and not params.use_fallback_tool) else _template_items_tool_select_actions(
+                "gpencil.select_lasso",
+                type=params.select_tweak if fallback else params.tool_tweak,
+                value='ANY')),
+            *_template_view3d_gpencil_select_for_fallback(params, fallback),
+        ]}
     )
 
 
@@ -7184,25 +7352,25 @@ def generate_keymaps(params=None):
 
         km_image_editor_tool_generic_sample(params),
         km_image_editor_tool_uv_cursor(params),
-        km_image_editor_tool_uv_select(params),
-        km_image_editor_tool_uv_select_box(params),
-        km_image_editor_tool_uv_select_circle(params),
-        km_image_editor_tool_uv_select_lasso(params),
+        *(km_image_editor_tool_uv_select(params, fallback=fallback) for fallback in (False, True)),
+        *(km_image_editor_tool_uv_select_box(params, fallback=fallback) for fallback in (False, True)),
+        *(km_image_editor_tool_uv_select_circle(params, fallback=fallback) for fallback in (False, True)),
+        *(km_image_editor_tool_uv_select_lasso(params, fallback=fallback) for fallback in (False, True)),
         km_image_editor_tool_uv_rip_region(params),
         km_image_editor_tool_uv_sculpt_stroke(params),
         km_image_editor_tool_uv_move(params),
         km_image_editor_tool_uv_rotate(params),
         km_image_editor_tool_uv_scale(params),
-        km_node_editor_tool_select(params),
-        km_node_editor_tool_select_box(params),
-        km_node_editor_tool_select_lasso(params),
-        km_node_editor_tool_select_circle(params),
+        *(km_node_editor_tool_select(params, fallback=fallback) for fallback in (False, True)),
+        *(km_node_editor_tool_select_box(params, fallback=fallback) for fallback in (False, True)),
+        *(km_node_editor_tool_select_lasso(params, fallback=fallback) for fallback in (False, True)),
+        *(km_node_editor_tool_select_circle(params, fallback=fallback) for fallback in (False, True)),
         km_node_editor_tool_links_cut(params),
         km_3d_view_tool_cursor(params),
-        km_3d_view_tool_select(params),
-        km_3d_view_tool_select_box(params),
-        km_3d_view_tool_select_circle(params),
-        km_3d_view_tool_select_lasso(params),
+        *(km_3d_view_tool_select(params, fallback=fallback) for fallback in (False, True)),
+        *(km_3d_view_tool_select_box(params, fallback=fallback) for fallback in (False, True)),
+        *(km_3d_view_tool_select_circle(params, fallback=fallback) for fallback in (False, True)),
+        *(km_3d_view_tool_select_lasso(params, fallback=fallback) for fallback in (False, True)),
         km_3d_view_tool_transform(params),
         km_3d_view_tool_move(params),
         km_3d_view_tool_rotate(params),
@@ -7273,10 +7441,10 @@ def generate_keymaps(params=None):
         km_3d_view_tool_paint_gpencil_cutter(params),
         km_3d_view_tool_paint_gpencil_eyedropper(params),
         km_3d_view_tool_paint_gpencil_interpolate(params),
-        km_3d_view_tool_edit_gpencil_select(params),
-        km_3d_view_tool_edit_gpencil_select_box(params),
-        km_3d_view_tool_edit_gpencil_select_circle(params),
-        km_3d_view_tool_edit_gpencil_select_lasso(params),
+        *(km_3d_view_tool_edit_gpencil_select(params, fallback=fallback) for fallback in (False, True)),
+        *(km_3d_view_tool_edit_gpencil_select_box(params, fallback=fallback) for fallback in (False, True)),
+        *(km_3d_view_tool_edit_gpencil_select_circle(params, fallback=fallback) for fallback in (False, True)),
+        *(km_3d_view_tool_edit_gpencil_select_lasso(params, fallback=fallback) for fallback in (False, True)),
         km_3d_view_tool_edit_gpencil_extrude(params),
         km_3d_view_tool_edit_gpencil_radius(params),
         km_3d_view_tool_edit_gpencil_bend(params),
diff --git a/release/scripts/startup/bl_ui/space_toolsystem_common.py b/release/scripts/startup/bl_ui/space_toolsystem_common.py
index 28549098e51..1c3dbded083 100644
--- a/release/scripts/startup/bl_ui/space_toolsystem_common.py
+++ b/release/scripts/startup/bl_ui/space_toolsystem_common.py
@@ -118,6 +118,8 @@ ToolDef = namedtuple(
         "draw_settings",
         # Optional draw cursor.
         "draw_cursor",
+        # Various options, see: `bpy.types.WorkSpaceTool.setup` options argument.
+        "options",
     )
 )
 del namedtuple
@@ -133,6 +135,7 @@ def from_dict(kw_args):
         "description": None,
         "icon": None,
         "cursor": None,
+        "options": None,
         "widget": None,
         "widget_properties": None,
         "keymap": None,
@@ -536,6 +539,7 @@ class ToolSelectPanelHelper:
                     visited.add(km_name)
 
                     yield (km_name, cls.bl_space_type, 'WINDOW', [])
+                    yield (km_name + " (fallback)", cls.bl_space_type, 'WINDOW', [])
 
     # -------------------------------------------------------------------------
     # Layout Generators
@@ -988,16 +992,22 @@ def _activate_by_item(context, space_type, item, index, *, as_fallback=False):
 
     gizmo_group = item.widget or ""
 
+    idname_fallback = (item_fallback and item_fallback.idname) or ""
+    keymap_fallback = (item_fallback and item_fallback.keymap and item_fallback.keymap[0]) or ""
+    if keymap_fallback:
+        keymap_fallback = keymap_fallback + " (fallback)"
+
     tool.setup(
         idname=item.idname,
         keymap=item.keymap[0] if item.keymap is not None else "",
         cursor=item.cursor or 'DEFAULT',
+        options=item.options or set(),
         gizmo_group=gizmo_group,
         data_block=item.data_block or "",
         operator=item.operator or "",
         index=index,
-        idname_fallback=(item_fallback and item_fallback.idname) or "",
-        keymap_fallback=(item_fallback and item_fallback.keymap and item_fallback.keymap[0]) or "",
+        idname_fallback=idname_fallback,
+        keymap_fallback=keymap_fallback,
     )
 
     if (
diff --git a/release/scripts/startup/bl_ui/space_toolsystem_toolbar.py b/release/scripts/startup/bl_ui/space_toolsystem_toolbar.py
index c5191e80aef..a513ab4b2d4 100644
--- a/release/scripts/startup/bl_ui/space_toolsystem_toolbar.py
+++ b/release/scripts/startup/bl_ui/space_toolsystem_toolbar.py
@@ -105,6 +105,7 @@ class _defs_view3d_generic:
             icon="ops.generic.cursor",
             keymap="3D View Tool: Cursor",
             draw_settings=draw_settings,
+            options={'KEYMAP_FALLBACK'},
         )
 
     @ToolDef.from_fn
@@ -143,6 +144,7 @@ class _defs_view3d_generic:
             icon="ops.view3d.ruler",
             widget="VIEW3D_GGT_ruler",
             keymap="3D View Tool: Measure",
+            options={'KEYMAP_FALLBACK'},
         )
 
 
@@ -237,6 +239,7 @@ class _defs_annotate:
             cursor='PAINT_BRUSH',
             keymap="Generic Tool: Annotate",
             draw_settings=draw_settings,
+            options={'KEYMAP_FALLBACK'},
         )
 
     @ToolDef.from_fn.with_args(draw_settings=draw_settings_common)
@@ -248,6 +251,7 @@ class _defs_annotate:
             cursor='PAINT_BRUSH',
             keymap="Generic Tool: Annotate Line",
             draw_settings=draw_settings,
+            options={'KEYMAP_FALLBACK'},
         )
 
     @ToolDef.from_fn.with_args(draw_settings=draw_settings_common)
@@ -259,6 +263,7 @@ class _defs_annotate:
             cursor='PAINT_BRUSH',
             keymap="Generic Tool: Annotate Polygon",
             draw_settings=draw_settings,
+            options={'KEYMAP_FALLBACK'},
         )
 
     @ToolDef.from_fn
@@ -274,6 +279,7 @@ class _defs_annotate:
             cursor='ERASER',
             keymap="Generic Tool: Annotate Eraser",
             draw_settings=draw_settings,
+            options={'KEYMAP_FALLBACK'},
         )
 
 
@@ -543,6 +549,7 @@ class _defs_view3d_add:
             widget="VIEW3D_GGT_placement",
             keymap="3D View Tool: Object, Add Primitive",
             draw_settings=draw_settings,
+            options={'KEYMAP_FALLBACK'},
         )
 
     @ToolDef.from_fn
@@ -569,6 +576,7 @@ class _defs_view3d_add:
             widget="VIEW3D_GGT_placement",
             keymap="3D View Tool: Object, Add Primitive",
             draw_settings=draw_settings,
+            options={'KEYMAP_FALLBACK'},
         )
 
     @ToolDef.from_fn
@@ -594,6 +602,7 @@ class _defs_view3d_add:
             widget="VIEW3D_GGT_placement",
             keymap="3D View Tool: Object, Add Primitive",
             draw_settings=draw_settings,
+            options={'KEYMAP_FALLBACK'},
         )
 
     @ToolDef.from_fn
@@ -619,6 +628,7 @@ class _defs_view3d_add:
             widget="VIEW3D_GGT_placement",
             keymap="3D View Tool: Object, Add Primitive",
             draw_settings=draw_settings,
+            options={'KEYMAP_FALLBACK'},
         )
 
     @ToolDef.from_fn
@@ -643,6 +653,7 @@ class _defs_view3d_add:
             widget="VIEW3D_GGT_placement",
             keymap="3D View Tool: Object, Add Primitive",
             draw_settings=draw_settings,
+            options={'KEYMAP_FALLBACK'},
         )
 
 
@@ -1089,6 +1100,7 @@ class _defs_edit_mesh:
             widget=None,
             keymap=(),
             draw_settings=draw_settings,
+            options={'KEYMAP_FALLBACK'},
         )
 
     @ToolDef.from_fn
@@ -1695,6 +1707,7 @@ class _defs_image_generic:
             ),
             icon="ops.generic.cursor",
             keymap=(),
+            options={'KEYMAP_FALLBACK'},
         )
 
     # Currently a place holder so we can switch away from the annotation tool.
@@ -1846,6 +1859,7 @@ class _defs_image_uv_edit:
             # TODO: generic operator (UV version of `VIEW3D_GGT_tool_generic_handle_free`).
             widget=None,
             keymap=(),
+            options={'KEYMAP_FALLBACK'},
         )
 
 
@@ -1879,6 +1893,7 @@ class _defs_image_uv_sculpt:
                 operator="sculpt.uv_sculpt_stroke",
                 keymap="Image Editor Tool: Uv, Sculpt Stroke",
                 draw_cursor=draw_cursor,
+                options={'KEYMAP_FALLBACK'},
             ),
         )
 
diff --git a/source/blender/editors/interface/interface_template_search_menu.c b/source/blender/editors/interface/interface_template_search_menu.c
index 672f1b64943..3a5d65475f7 100644
--- a/source/blender/editors/interface/interface_template_search_menu.c
+++ b/source/blender/editors/interface/interface_template_search_menu.c
@@ -350,24 +350,28 @@ static void menu_types_add_from_keymap_items(bContext *C,
 
       if (handler_base->poll == NULL || handler_base->poll(region, win->eventstate)) {
         wmEventHandler_Keymap *handler = (wmEventHandler_Keymap *)handler_base;
-        wmKeyMap *keymap = WM_event_get_keymap_from_handler(wm, handler);
-        if (keymap && WM_keymap_poll(C, keymap)) {
-          LISTBASE_FOREACH (wmKeyMapItem *, kmi, &keymap->items) {
-            if (kmi->flag & KMI_INACTIVE) {
-              continue;
-            }
-            if (STR_ELEM(kmi->idname, "WM_OT_call_menu", "WM_OT_call_menu_pie")) {
-              char menu_idname[MAX_NAME];
-              RNA_string_get(kmi->ptr, "name", menu_idname);
-              MenuType *mt = WM_menutype_find(menu_idname, false);
-
-              if (mt && BLI_gset_add(menu_tagged, mt)) {
-                /* Unlikely, but possible this will be included twice. */
-                BLI_linklist_prepend(menuid_stack_p, mt);
-
-                void **kmi_p;
-                if (!BLI_ghash_ensure_p(menu_to_kmi, mt, &kmi_p)) {
-                  *kmi_p = kmi;
+        wmEventHandler_KeymapResult km_result;
+        WM_event_get_keymaps_from_handler(wm, handler, &km_result);
+        for (int km_index = 0; km_index < km_result.keymaps_len; km_index++) {
+          wmKeyMap *keymap = km_result.keymaps[km_index];
+          if (keymap && WM_keymap_poll(C, keymap)) {
+            LISTBASE_FOREACH (wmKeyMapItem *, kmi, &keymap->items) {
+              if (kmi->flag & KMI_INACTIVE) {
+                continue;
+              }
+              if (STR_ELEM(kmi->idname, "WM_OT_call_menu", "WM_OT_call_menu_pie")) {
+                char menu_idname[MAX_NAME];
+                RNA_string_get(kmi->ptr, "name", menu_idname);
+                MenuType *mt = WM_menutype_find(menu_idname, false);
+
+                if (mt && BLI_gset_add(menu_tagged, mt)) {
+                  /* Unlikely, but possible this will be included twice. */
+                  BLI_linklist_prepend(menuid_stack_p, mt);
+
+                  void **kmi_p;
+                  if (!BLI_ghash_ensure_p(menu_to_kmi, mt, &kmi_p)) {
+                    *kmi_p = kmi;
+                  }
                 }
               }
             }
diff --git a/source/blender/editors/mesh/editmesh_extrude_spin_gizmo.c b/source/blender/editors/mesh/editmesh_extrude_spin_gizmo.c
index ae37d6c8deb..5faafa77bba 100644
--- a/source/blender/editors/mesh/editmesh_extrude_spin_gizmo.c
+++ b/source/blender/editors/mesh/editmesh_extrude_spin_gizmo.c
@@ -461,7 +461,7 @@ void MESH_GGT_spin(struct wmGizmoGroupType *gzgt)
   gzgt->name = "Mesh Spin Init";
   gzgt->idname = "MESH_GGT_spin";
 
-  gzgt->flag = WM_GIZMOGROUPTYPE_3D;
+  gzgt->flag = WM_GIZMOGROUPTYPE_TOOL_FALLBACK_KEYMAP | WM_GIZMOGROUPTYPE_3D;
 
   gzgt->gzmap_params.spaceid = SPACE_VIEW3D;
   gzgt->gzmap_params.regionid = RGN_TYPE_WINDOW;
@@ -1063,7 +1063,7 @@ void MESH_GGT_spin_redo(struct wmGizmoGroupType *gzgt)
   gzgt->name = "Mesh Spin Redo";
   gzgt->idname = "MESH_GGT_spin_redo";
 
-  gzgt->flag = WM_GIZMOGROUPTYPE_3D;
+  gzgt->flag = WM_GIZMOGROUPTYPE_TOOL_FALLBACK_KEYMAP | WM_GIZMOGROUPTYPE_3D;
 
   gzgt->gzmap_params.spaceid = SPACE_VIEW3D;
   gzgt->gzmap_params.regionid = RGN_TYPE_WINDOW;
diff --git a/source/blender/editors/screen/area.c b/source/blender/editors/screen/area.c
index 9546035375c..c71e68df2fd 100644
--- a/source/blender/editors/screen/area.c
+++ b/source/blender/editors/screen/area.c
@@ -1735,10 +1735,14 @@ static void ed_default_handlers(
     WM_event_add_keymap_handler(handlers, keymap);
   }
   if (flag & ED_KEYMAP_TOOL) {
-    WM_event_add_keymap_handler_dynamic(
-        &region->handlers, WM_event_get_keymap_from_toolsystem_fallback, area);
-    WM_event_add_keymap_handler_dynamic(
-        &region->handlers, WM_event_get_keymap_from_toolsystem, area);
+    if (flag & ED_KEYMAP_GIZMO) {
+      WM_event_add_keymap_handler_dynamic(
+          &region->handlers, WM_event_get_keymap_from_toolsystem_fallback, area);
+    }
+    else {
+      WM_event_add_keymap_handler_dynamic(
+          &region->handlers, WM_event_get_keymap_from_toolsystem, area);
+    }
   }
   if (flag & ED_KEYMAP_FRAMES) {
     /* frame changing/jumping (for all spaces) */
diff --git a/source/blender/editors/space_view3d/view3d_gizmo_preselect.c b/source/blender/editors/space_view3d/view3d_gizmo_preselect.c
index 441182d7a5f..918ecb14752 100644
--- a/source/blender/editors/space_view3d/view3d_gizmo_preselect.c
+++ b/source/blender/editors/space_view3d/view3d_gizmo_preselect.c
@@ -58,7 +58,7 @@ void VIEW3D_GGT_mesh_preselect_elem(wmGizmoGroupType *gzgt)
   gzgt->name = "Mesh Preselect Element";
   gzgt->idname = "VIEW3D_GGT_mesh_preselect_elem";
 
-  gzgt->flag = WM_GIZMOGROUPTYPE_3D;
+  gzgt->flag = WM_GIZMOGROUPTYPE_TOOL_FALLBACK_KEYMAP | WM_GIZMOGROUPTYPE_3D;
 
   gzgt->gzmap_params.spaceid = SPACE_VIEW3D;
   gzgt->gzmap_params.regionid = RGN_TYPE_WINDOW;
@@ -95,7 +95,7 @@ void VIEW3D_GGT_mesh_preselect_edgering(wmGizmoGroupType *gzgt)
   gzgt->name = "Mesh Preselect Edge Ring";
   gzgt->idname = "VIEW3D_GGT_mesh_preselect_edgering";
 
-  gzgt->flag = WM_GIZMOGROUPTYPE_3D;
+  gzgt->flag = WM_GIZMOGROUPTYPE_TOOL_FALLBACK_KEYMAP | WM_GIZMOGROUPTYPE_3D;
 
   gzgt->gzmap_params.spaceid = SPACE_VIEW3D;
   gzgt->gzmap_params.regionid = RGN_TYPE_WINDOW;
diff --git a/source/blender/makesdna/DNA_workspace_types.h b/source/blender/makesdna/DNA_workspace_types.h
index e0294d3534c..a0856588a58 100644
--- a/source/blender/makesdna/DNA_workspace_types.h
+++ b/source/blender/makesdna/DNA_workspace_types.h
@@ -29,6 +29,15 @@
 extern "C" {
 #endif
 
+/** #bToolRef_Runtime.flag */
+enum {
+  /**
+   * This tool should use the fallback key-map.
+   * Typically gizmos handle this but some tools (such as the knife tool) don't use a gizmo.
+   */
+  TOOLREF_FLAG_FALLBACK_KEYMAP = (1 << 0),
+};
+
 #
 #
 typedef struct bToolRef_Runtime {
@@ -47,6 +56,8 @@ typedef struct bToolRef_Runtime {
 
   /** Index when a tool is a member of a group. */
   int index;
+  /** Options: `TOOLREF_FLAG_*`. */
+  int flag;
 } bToolRef_Runtime;
 
 /* Stored per mode. */
diff --git a/source/blender/makesrna/intern/rna_workspace_api.c b/source/blender/makesrna/intern/rna_workspace_api.c
index a2bb89dd5ee..15230f1198b 100644
--- a/source/blender/makesrna/intern/rna_workspace_api.c
+++ b/source/blender/makesrna/intern/rna_workspace_api.c
@@ -29,6 +29,7 @@
 
 #include "DNA_object_types.h"
 #include "DNA_windowmanager_types.h"
+#include "DNA_workspace_types.h"
 
 #include "RNA_enum_types.h" /* own include */
 
@@ -51,6 +52,7 @@ static void rna_WorkSpaceTool_setup(ID *id,
                                     const char *data_block,
                                     const char *op_idname,
                                     int index,
+                                    int options,
                                     const char *idname_fallback,
                                     const char *keymap_fallback)
 {
@@ -62,6 +64,7 @@ static void rna_WorkSpaceTool_setup(ID *id,
   STRNCPY(tref_rt.data_block, data_block);
   STRNCPY(tref_rt.op, op_idname);
   tref_rt.index = index;
+  tref_rt.flag = options;
 
   /* While it's logical to assign both these values from setup,
    * it's useful to stored this in DNA for re-use, exceptional case: write to the 'tref'. */
@@ -131,6 +134,11 @@ void RNA_api_workspace_tool(StructRNA *srna)
   PropertyRNA *parm;
   FunctionRNA *func;
 
+  static EnumPropertyItem options_items[] = {
+      {TOOLREF_FLAG_FALLBACK_KEYMAP, "KEYMAP_FALLBACK", 0, "Fallback", ""},
+      {0, NULL, 0, NULL, NULL},
+  };
+
   func = RNA_def_function(srna, "setup", "rna_WorkSpaceTool_setup");
   RNA_def_function_flag(func, FUNC_USE_SELF_ID | FUNC_USE_CONTEXT);
   RNA_def_function_ui_description(func, "Set the tool settings");
@@ -146,6 +154,7 @@ void RNA_api_workspace_tool(StructRNA *srna)
   RNA_def_string(func, "data_block", NULL, MAX_NAME, "Data Block", "");
   RNA_def_string(func, "operator", NULL, MAX_NAME, "Operator", "");
   RNA_def_int(func, "index", 0, INT_MIN, INT_MAX, "Index", "", INT_MIN, INT_MAX);
+  RNA_def_enum_flag(func, "options", options_items, 0, "Tool Options", "");
 
   RNA_def_string(func, "idname_fallback", NULL, MAX_NAME, "Fallback Identifier", "");
   RNA_def_string(func, "keymap_fallback", NULL, KMAP_MAX_NAME, "Fallback Key Map", "");
diff --git a/source/blender/windowmanager/WM_api.h b/source/blender/windowmanager/WM_api.h
index 28d3cb326ae..4fe1530628b 100644
--- a/source/blender/windowmanager/WM_api.h
+++ b/source/blender/windowmanager/WM_api.h
@@ -262,14 +262,21 @@ struct wmEventHandler_Keymap *WM_event_add_keymap_handler_priority(ListBase *han
                                                                    wmKeyMap *keymap,
                                                                    int priority);
 
-typedef struct wmKeyMap *(wmEventHandler_KeymapDynamicFn)(wmWindowManager *wm,
-                                                          struct wmEventHandler_Keymap *handler)
-    ATTR_WARN_UNUSED_RESULT;
-
-struct wmKeyMap *WM_event_get_keymap_from_toolsystem_fallback(
-    struct wmWindowManager *wm, struct wmEventHandler_Keymap *handler);
-struct wmKeyMap *WM_event_get_keymap_from_toolsystem(struct wmWindowManager *wm,
-                                                     struct wmEventHandler_Keymap *handler);
+typedef struct wmEventHandler_KeymapResult {
+  wmKeyMap *keymaps[3];
+  int keymaps_len;
+} wmEventHandler_KeymapResult;
+
+typedef void(wmEventHandler_KeymapDynamicFn)(wmWindowManager *wm,
+                                             struct wmEventHandler_Keymap *handler,
+                                             struct wmEventHandler_KeymapResult *km_result);
+
+void WM_event_get_keymap_from_toolsystem_fallback(struct wmWindowManager *wm,
+                                                  struct wmEventHandler_Keymap *handler,
+                                                  wmEventHandler_KeymapResult *km_result);
+void WM_event_get_keymap_from_toolsystem(struct wmWindowManager *wm,
+                                         struct wmEventHandler_Keymap *handler,
+                                         wmEventHandler_KeymapResult *km_result);
 
 struct wmEventHandler_Keymap *WM_event_add_keymap_handler_dynamic(
     ListBase *handlers, wmEventHandler_KeymapDynamicFn *keymap_fn, void *user_data);
@@ -281,8 +288,9 @@ void WM_event_set_keymap_handler_post_callback(struct wmEventHandler_Keymap *han
                                                                 wmKeyMapItem *kmi,
                                                                 void *user_data),
                                                void *user_data);
-wmKeyMap *WM_event_get_keymap_from_handler(wmWindowManager *wm,
-                                           struct wmEventHandler_Keymap *handler);
+void WM_event_get_keymaps_from_handler(wmWindowManager *wm,
+                                       struct wmEventHandler_Keymap *handler,
+                                       struct wmEventHandler_KeymapResult *km_result);
 
 wmKeyMapItem *WM_event_match_keymap_item(struct bContext *C,
                                          wmKeyMap *keymap,
diff --git a/source/blender/windowmanager/gizmo/intern/wm_gizmo_group.c b/source/blender/windowmanager/gizmo/intern/wm_gizmo_group.c
index 213a3c2e342..22bdf65a169 100644
--- a/source/blender/windowmanager/gizmo/intern/wm_gizmo_group.c
+++ b/source/blender/windowmanager/gizmo/intern/wm_gizmo_group.c
@@ -265,6 +265,8 @@ void WM_gizmogroup_ensure_init(const bContext *C, wmGizmoGroup *gzgroup)
 {
   /* prepare for first draw */
   if (UNLIKELY((gzgroup->init_flag & WM_GIZMOGROUP_INIT_SETUP) == 0)) {
+
+    gzgroup->use_fallback_keymap = true;
     gzgroup->type->setup(C, gzgroup);
 
     /* Not ideal, initialize keymap here, needed for RNA runtime generated gizmos. */
diff --git a/source/blender/windowmanager/intern/wm_event_system.c b/source/blender/windowmanager/intern/wm_event_system.c
index ae09786356a..14fcc1d69cc 100644
--- a/source/blender/windowmanager/intern/wm_event_system.c
+++ b/source/blender/windowmanager/intern/wm_event_system.c
@@ -2989,9 +2989,18 @@ static int wm_handlers_do_intern(bContext *C, wmEvent *event, ListBase *handlers
       /* Handle all types here. */
       if (handler_base->type == WM_HANDLER_TYPE_KEYMAP) {
         wmEventHandler_Keymap *handler = (wmEventHandler_Keymap *)handler_base;
-        wmKeyMap *keymap = WM_event_get_keymap_from_handler(wm, handler);
-        action |= wm_handlers_do_keymap_with_keymap_handler(
-            C, event, handlers, handler, keymap, do_debug_handler);
+        wmEventHandler_KeymapResult km_result;
+        WM_event_get_keymaps_from_handler(wm, handler, &km_result);
+        int action_iter = WM_HANDLER_CONTINUE;
+        for (int km_index = 0; km_index < km_result.keymaps_len; km_index++) {
+          wmKeyMap *keymap = km_result.keymaps[km_index];
+          action_iter |= wm_handlers_do_keymap_with_keymap_handler(
+              C, event, handlers, handler, keymap, do_debug_handler);
+          if (action_iter & WM_HANDLER_BREAK) {
+            break;
+          }
+        }
+        action |= action_iter;
 
         /* Clear the tool-tip whenever a key binding is handled, without this tool-tips
          * are kept when a modal operators starts (annoying but otherwise harmless). */
@@ -3905,17 +3914,34 @@ wmEventHandler_Keymap *WM_event_add_keymap_handler(ListBase *handlers, wmKeyMap
  *
  * Follow #wmEventHandler_KeymapDynamicFn signature.
  */
-wmKeyMap *WM_event_get_keymap_from_toolsystem_fallback(wmWindowManager *wm,
-                                                       wmEventHandler_Keymap *handler)
+void WM_event_get_keymap_from_toolsystem_fallback(wmWindowManager *wm,
+                                                  wmEventHandler_Keymap *handler,
+                                                  wmEventHandler_KeymapResult *km_result)
 {
+  memset(km_result, 0x0, sizeof(*km_result));
+
+  const char *keymap_id_list[ARRAY_SIZE(km_result->keymaps)];
+  int keymap_id_list_len = 0;
+
   ScrArea *area = handler->dynamic.user_data;
   handler->keymap_tool = NULL;
   bToolRef_Runtime *tref_rt = area->runtime.tool ? area->runtime.tool->runtime : NULL;
-  if (tref_rt && tref_rt->keymap_fallback[0]) {
-    const char *keymap_id = NULL;
 
+  if (tref_rt && tref_rt->keymap[0]) {
+    keymap_id_list[keymap_id_list_len++] = tref_rt->keymap;
+  }
+
+  bool is_gizmo_visible = false;
+  bool is_gizmo_highlight = false;
+
+  if (tref_rt && tref_rt->keymap_fallback[0]) {
+    bool add_keymap = false;
     /* Support for the gizmo owning the tool keymap. */
-    if (tref_rt->gizmo_group[0] != '\0' && tref_rt->keymap_fallback[0] != '\0') {
+
+    if (tref_rt->flag & TOOLREF_FLAG_FALLBACK_KEYMAP) {
+      add_keymap = true;
+    }
+    if (tref_rt->gizmo_group[0] != '\0') {
       wmGizmoMap *gzmap = NULL;
       wmGizmoGroup *gzgroup = NULL;
       LISTBASE_FOREACH (ARegion *, region, &area->regionbase) {
@@ -3931,32 +3957,49 @@ wmKeyMap *WM_event_get_keymap_from_toolsystem_fallback(wmWindowManager *wm,
         if (gzgroup->type->flag & WM_GIZMOGROUPTYPE_TOOL_FALLBACK_KEYMAP) {
           /* If all are hidden, don't override. */
           if (gzgroup->use_fallback_keymap) {
+            is_gizmo_visible = true;
             wmGizmo *highlight = wm_gizmomap_highlight_get(gzmap);
-            if (highlight == NULL) {
-              keymap_id = tref_rt->keymap_fallback;
+            if (highlight) {
+              is_gizmo_highlight = true;
             }
+            add_keymap = true;
           }
         }
       }
     }
+    if (add_keymap) {
+      keymap_id_list[keymap_id_list_len++] = tref_rt->keymap_fallback;
+    }
+  }
 
-    if (keymap_id && keymap_id[0]) {
-      wmKeyMap *km = WM_keymap_list_find_spaceid_or_empty(
-          &wm->userconf->keymaps, keymap_id, area->spacetype, RGN_TYPE_WINDOW);
-      /* We shouldn't use keymaps from unrelated spaces. */
-      if (km != NULL) {
-        handler->keymap_tool = area->runtime.tool;
-        return km;
-      }
-      printf(
-          "Keymap: '%s' not found for tool '%s'\n", tref_rt->keymap, area->runtime.tool->idname);
+  if (is_gizmo_visible && !is_gizmo_highlight) {
+    if (keymap_id_list_len == 2) {
+      SWAP(const char *, keymap_id_list[0], keymap_id_list[1]);
     }
   }
-  return NULL;
+
+  for (int i = 0; i < keymap_id_list_len; i++) {
+    const char *keymap_id = keymap_id_list[i];
+    BLI_assert(keymap_id && keymap_id[0]);
+
+    wmKeyMap *km = WM_keymap_list_find_spaceid_or_empty(
+        &wm->userconf->keymaps, keymap_id, area->spacetype, RGN_TYPE_WINDOW);
+    /* We shouldn't use keymaps from unrelated spaces. */
+    if (km == NULL) {
+      printf("Keymap: '%s' not found for tool '%s'\n", keymap_id, area->runtime.tool->idname);
+      continue;
+    }
+    handler->keymap_tool = area->runtime.tool;
+    km_result->keymaps[km_result->keymaps_len++] = km;
+  }
 }
 
-wmKeyMap *WM_event_get_keymap_from_toolsystem(wmWindowManager *wm, wmEventHandler_Keymap *handler)
+void WM_event_get_keymap_from_toolsystem(wmWindowManager *wm,
+                                         wmEventHandler_Keymap *handler,
+                                         wmEventHandler_KeymapResult *km_result)
 {
+  memset(km_result, 0x0, sizeof(*km_result));
+
   ScrArea *area = handler->dynamic.user_data;
   handler->keymap_tool = NULL;
   bToolRef_Runtime *tref_rt = area->runtime.tool ? area->runtime.tool->runtime : NULL;
@@ -3968,13 +4011,14 @@ wmKeyMap *WM_event_get_keymap_from_toolsystem(wmWindowManager *wm, wmEventHandle
       /* We shouldn't use keymaps from unrelated spaces. */
       if (km != NULL) {
         handler->keymap_tool = area->runtime.tool;
-        return km;
+        km_result->keymaps[km_result->keymaps_len++] = km;
+      }
+      else {
+        printf(
+            "Keymap: '%s' not found for tool '%s'\n", tref_rt->keymap, area->runtime.tool->idname);
       }
-      printf(
-          "Keymap: '%s' not found for tool '%s'\n", tref_rt->keymap, area->runtime.tool->idname);
     }
   }
-  return NULL;
 }
 
 struct wmEventHandler_Keymap *WM_event_add_keymap_handler_dynamic(
@@ -5088,18 +5132,22 @@ void WM_set_locked_interface(wmWindowManager *wm, bool lock)
 /** \name Event / Keymap Matching API
  * \{ */
 
-wmKeyMap *WM_event_get_keymap_from_handler(wmWindowManager *wm, wmEventHandler_Keymap *handler)
+void WM_event_get_keymaps_from_handler(wmWindowManager *wm,
+                                       wmEventHandler_Keymap *handler,
+                                       wmEventHandler_KeymapResult *km_result)
 {
-  wmKeyMap *keymap;
   if (handler->dynamic.keymap_fn != NULL) {
-    keymap = handler->dynamic.keymap_fn(wm, handler);
+    handler->dynamic.keymap_fn(wm, handler, km_result);
     BLI_assert(handler->keymap == NULL);
   }
   else {
-    keymap = WM_keymap_active(wm, handler->keymap);
+    memset(km_result, 0x0, sizeof(*km_result));
+    wmKeyMap *keymap = WM_keymap_active(wm, handler->keymap);
     BLI_assert(keymap != NULL);
+    if (keymap != NULL) {
+      km_result->keymaps[km_result->keymaps_len++] = keymap;
+    }
   }
-  return keymap;
 }
 
 wmKeyMapItem *WM_event_match_keymap_item(bContext *C, wmKeyMap *keymap, const wmEvent *event)
@@ -5128,11 +5176,15 @@ wmKeyMapItem *WM_event_match_keymap_item_from_handlers(bContext *C,
     else if (handler_base->poll == NULL || handler_base->poll(CTX_wm_region(C), event)) {
       if (handler_base->type == WM_HANDLER_TYPE_KEYMAP) {
         wmEventHandler_Keymap *handler = (wmEventHandler_Keymap *)handler_base;
-        wmKeyMap *keymap = WM_event_get_keymap_from_handler(wm, handler);
-        if (keymap && WM_keymap_poll(C, keymap)) {
-          wmKeyMapItem *kmi = WM_event_match_keymap_item(C, keymap, event);
-          if (kmi != NULL) {
-            return kmi;
+        wmEventHandler_KeymapResult km_result;
+        WM_event_get_keymaps_from_handler(wm, handler, &km_result);
+        for (int km_index = 0; km_index < km_result.keymaps_len; km_index++) {
+          wmKeyMap *keymap = km_result.keymaps[km_index];
+          if (WM_keymap_poll(C, keymap)) {
+            wmKeyMapItem *kmi = WM_event_match_keymap_item(C, keymap, event);
+            if (kmi != NULL) {
+              return kmi;
+            }
           }
         }
       }
diff --git a/source/blender/windowmanager/intern/wm_keymap.c b/source/blender/windowmanager/intern/wm_keymap.c
index f955abaed53..e5aedfc7f47 100644
--- a/source/blender/windowmanager/intern/wm_keymap.c
+++ b/source/blender/windowmanager/intern/wm_keymap.c
@@ -462,7 +462,9 @@ bool WM_keymap_poll(bContext *C, wmKeyMap *keymap)
     /* Empty key-maps may be missing more there may be a typo in the name.
      * Warn early to avoid losing time investigating each case.
      * When developing a customized Blender though you may want empty keymaps. */
-    if (!U.app_template[0]) {
+    if (!U.app_template[0] &&
+        /* Fallback key-maps may be intentionally empty, don't flood the output. */
+        !BLI_str_endswith(keymap->idname, " (fallback)")) {
       CLOG_WARN(WM_LOG_KEYMAPS, "empty keymap '%s'", keymap->idname);
     }
   }
@@ -1402,15 +1404,19 @@ static wmKeyMapItem *wm_keymap_item_find_handlers(const bContext *C,
   LISTBASE_FOREACH (wmEventHandler *, handler_base, handlers) {
     if (handler_base->type == WM_HANDLER_TYPE_KEYMAP) {
       wmEventHandler_Keymap *handler = (wmEventHandler_Keymap *)handler_base;
-      wmKeyMap *keymap = WM_event_get_keymap_from_handler(wm, handler);
-      if (keymap && WM_keymap_poll((bContext *)C, keymap)) {
-        wmKeyMapItem *kmi = wm_keymap_item_find_in_keymap(
-            keymap, opname, properties, is_strict, params);
-        if (kmi != NULL) {
-          if (r_keymap) {
-            *r_keymap = keymap;
+      wmEventHandler_KeymapResult km_result;
+      WM_event_get_keymaps_from_handler(wm, handler, &km_result);
+      for (int km_index = 0; km_index < km_result.keymaps_len; km_index++) {
+        wmKeyMap *keymap = km_result.keymaps[km_index];
+        if (WM_keymap_poll((bContext *)C, keymap)) {
+          wmKeyMapItem *kmi = wm_keymap_item_find_in_keymap(
+              keymap, opname, properties, is_strict, params);
+          if (kmi != NULL) {
+            if (r_keymap) {
+              *r_keymap = keymap;
+            }
+            return kmi;
           }
-          return kmi;
         }
       }
     }
diff --git a/source/blender/windowmanager/intern/wm_toolsystem.c b/source/blender/windowmanager/intern/wm_toolsystem.c
index 5eaf026191f..0c24520d565 100644
--- a/source/blender/windowmanager/intern/wm_toolsystem.c
+++ b/source/blender/windowmanager/intern/wm_toolsystem.c
@@ -326,7 +326,10 @@ void WM_toolsystem_ref_set_from_runtime(struct bContext *C,
   bool use_fallback_keymap = false;
 
   if (tref->idname_fallback[0] || tref->runtime->keymap_fallback[0]) {
-    if (tref_rt->gizmo_group[0]) {
+    if (tref_rt->flag & TOOLREF_FLAG_FALLBACK_KEYMAP) {
+      use_fallback_keymap = true;
+    }
+    else if (tref_rt->gizmo_group[0]) {
       wmGizmoGroupType *gzgt = WM_gizmogrouptype_find(tref_rt->gizmo_group, false);
       if (gzgt) {
         if (gzgt->flag & WM_GIZMOGROUPTYPE_TOOL_FALLBACK_KEYMAP) {