### Godot version

v4.0.beta12.official [3c9bf4bc2]

### System information

Windows 10, AMD Radeon RX 480 4 GB RAM, 16 gb ram, Intel CPU 4 cores.

### Issue description


When switching to mobile render from forward + The alpha texture on the tree mesh starts to flicker.
Made a video: https://www.youtube.com/watch?v=WdGVi1hdRHo



### Steps to reproduce

Switching to mobile render from forward +

### Minimal reproduction project

Uploaded the project in google link: https://drive.google.com/file/d/1efEV914CWkyWoGzkv3RBMnw9t-4BVTeQ/view?usp=sharing
(only deleted the .godot - i guess its not needed.)
if (!can_draw_3d) {
					RSG::scene->render_empty_scene(p_viewport->render_buffers, p_viewport->scenario, p_viewport->shadow_atlas);
				} else {
					_draw_3d(p_viewport);
				}
				scenario_draw_canvas_bg = false;
			}
		}
		if (scenario_draw_canvas_bg) {
			
			
			RSG::texture_storage->render_target_do_clear_request(p_viewport->render_target);
			if (!can_draw_3d) {
				RSG::scene->render_empty_scene(p_viewport->render_buffers, p_viewport->scenario, p_viewport->shadow_atlas);
			} else {
				_draw_3d(p_viewport);
			}
		}
	}
	if (RSG::texture_storage->render_target_is_clear_requested(p_viewport->render_target)) {
		
		RSG::texture_storage->render_target_do_clear_request(p_viewport->render_target);
	}
	if (p_viewport->measure_render_time) {
		String rt_id = "vp_end_" + itos(p_viewport->self.get_id());
		RSG::utilities->capture_timestamp(rt_id);
		timestamp_vp_map[rt_id] = p_viewport->self;
	}
}
void RendererViewport::draw_viewports() {