Рефактор. Потому что приборы!

scenes/button-flat/button-flat.tscn

@@ -132,6 +132,7 @@ theme_override_styles/hover = SubResource("2")
 theme_override_styles/pressed = SubResource("3")
 theme_override_styles/disabled = SubResource("5")
 theme_override_styles/focus = SubResource("4")
+toggle_mode = true
 clip_text = true
 
 [connection signal="resized" from="." to="." method="_on_resized"]

scenes/button-flat/nine-patch-button.gd

@@ -19,9 +19,11 @@ func is_toggle_mode(): return $button.is_toggle_mode()
     set(val): $state.set_texture(val)
 
 
-@export var strips_rotation: float:
-    set(val): $back.strips_rotation = deg_to_rad(val)
-    get: return rad_to_deg($back.strips_rotation)
+@export var strips_rotation: float = 0.0:
+    set(val):
+        strips_rotation = val
+        $back.strips_rotation = deg_to_rad(val)
+    get: return strips_rotation
 
 
 @export var text: String = '':
@@ -31,20 +33,27 @@ func is_toggle_mode(): return $button.is_toggle_mode()
 
 @export var disabled: bool = false:
     set(val):
+        disabled = val
         $button.set_disabled(val)
         $back.disabled = val
         $state.modulate.a = 0.5 if val else 1.0
-    get: return $button.disabled
+    get: return disabled
 
 
 @export var pressed: bool = false:
-    set(val):   $button.set_pressed(val)
-    get: return $button.is_pressed()
+    set(val):
+        pressed = val
+        $button.set_pressed(val)
+    get:
+        return pressed
 
 
-@export var toggle_mode: bool:
-    set(val):   $button.set_toggle_mode(val)
-    get: return $button.is_toggle_mode()
+@export var toggle_mode: bool = false:
+    set(val):
+        toggle_mode = val
+        $button.set_toggle_mode(val)
+    get:
+        return toggle_mode
 
 
 func _on_resized() -> void:
@@ -59,7 +68,7 @@ func _enter_tree() -> void:
     $button.connect('toggled', Callable(self, '_on_button_toggled'))
 
 
-func set_toggle_mode (val: bool):
+func set_toggle_mode(val: bool):
     $button.set_toggle_mode(val)