### Godot version

4.2.beta.custom_build [51f81e1c8]

### System information

macOS 11.0+

### Issue description

I could sense a recent merging of a few pull requests on here:

<img width="865" alt="image" src="https://github.com/godotengine/godot/assets/1129695/1cf7d144-a4d2-4514-abca-1405222e702a">

This bug has the following related merges as the most recent ones:

https://github.com/godotengine/godot/pull/80813
https://github.com/godotengine/godot/pull/80939

The pull requests are for reviving onion-skinning capabilities, but this causes a minor unexpected result (see Steps to reproduce)



### Steps to reproduce

## A. Use 4.2.beta.custom_build [51f81e1c8]

1. Obtain the attached minimal reproduction project
2. Select the AnimationPlayer node
<img width="1468" alt="image" src="https://github.com/godotengine/godot/assets/1129695/ca16d7a6-7690-45b4-b8f9-b12fded64ca4">
3. In the Animation panel, click "Edit" to find your shortcuts for "Go to Next Step" and "Go to Previous Step"
<img width="410" alt="image" src="https://github.com/godotengine/godot/assets/1129695/a708e196-2eb9-42ea-bf0e-fd0aa88a9e60">
4. Use the shortcuts to spam go back and forth the animation

Expected result: animation goes smoothly

https://github.com/godotengine/godot/assets/1129695/c24c498c-7f77-4cc9-a1c9-a1627d89c58b



Actual result: animation jumps crazily


https://github.com/godotengine/godot/assets/1129695/947bf5b4-a0ab-42d4-bb5b-201800b4bdc6


https://github.com/godotengine/godot/assets/1129695/65303cd0-8c2d-4a35-9d16-c94752ac2e3a




## B. My successful yet unverified fix attempt on 4.2.beta.custom_build [51f81e1c8]

Either by:

<img width="831" alt="image" src="https://github.com/godotengine/godot/assets/1129695/80d167ae-27e7-4ec4-a4c9-ffc7adc0353f">


Or by:

<img width="806" alt="image" src="https://github.com/godotengine/godot/assets/1129695/2bae8697-8ef3-48dc-9f0a-2b5fe568ed43">


I don't see any negative impact on Onion Skinning or other functions by the above fix attempt, but I am not sure, I need someone to help me verify this.



### Minimal reproduction project

[gd_anim_unittest_1.zip](https://github.com/godotengine/godot/files/12909805/gd_anim_unittest_1.zip)






}
	
	RID root_vp = get_tree()->get_root()->get_viewport_rid();
	onion.temp.screen_rect = Rect2(Vector2(), DisplayServer::get_singleton()->window_get_size(DisplayServer::MAIN_WINDOW_ID));
	RS::get_singleton()->viewport_attach_to_screen(root_vp, Rect2(), DisplayServer::INVALID_WINDOW_ID);
	RS::get_singleton()->viewport_set_update_mode(root_vp, RS::VIEWPORT_UPDATE_ALWAYS);
	RID present_rid;
	if (onion.differences_only) {
		
		RS::get_singleton()->canvas_item_set_material(onion.capture.canvas_item, RID());
		present_rid = onion.captures[onion.captures.size() - 1];
		RS::get_singleton()->viewport_set_active(present_rid, true);
		RS::get_singleton()->viewport_set_parent_viewport(root_vp, present_rid);
		RS::get_singleton()->draw(false);
		RS::get_singleton()->viewport_set_active(present_rid, false);
	}
	
	onion.temp.anim_values_backup = player->make_backup();
	onion.temp.anim_player_position = player->get_current_animation_position();
	
	RS::get_singleton()->canvas_item_set_material(onion.capture.canvas_item, onion.capture.material->get_rid());
	onion.capture.material->set_shader_parameter("bkg_color", GLOBAL_GET("rendering/environment/defaults/default_clear_color"));
	onion.capture.material->set_shader_parameter("differences_only", onion.differences_only);
	onion.capture.material->set_shader_parameter("present", onion.differences_only ? RS::get_singleton()->viewport_get_texture(present_rid) : RID());
	onion.capture.material->set_shader_parameter("dir_color", onion.force_white_modulate ? Color(1, 1, 1) : Color(EDITOR_GET("editors/animation/onion_layers_past_color")));
	uint32_t p_capture_idx = 0;
	int first_step_offset = onion.past ? -(int)onion.steps : 0;
	_prepare_onion_layers_2_step_prepare(first_step_offset, p_capture_idx);
}
void AnimationPlayerEditor::_prepare_onion_layers_2_step_prepare(int p_step_offset, uint32_t p_capture_idx) {