### Godot version

4.1.1.stable, 4.2.dev (2282fc5de)

### System information

Arch Linux - X11 - GLES3 (Compatibility) - NVIDIA GeForce RTX 3060 Ti (nvidia; 535.104.05) - 13th Gen Intel(R) Core(TM) i5-13400F (16 Threads)

### Issue description

When using Compatibility renderer, adjusting the Alpha component of clear color affects 2D editor content.

This does not happen when using Forward+ or Mobile renderer. Does not affect 3D editor and the running game.


https://github.com/godotengine/godot/assets/372476/e398522e-590a-4832-959f-ea8ba8e71c5d



### Steps to reproduce

1. Create a project using Compatibility renderer.
2. Adjust the clear color's alpha component in Project Settings.

### Minimal reproduction project

N/A
state.canvas_instance_batches[state.current_batch_index].command = c;
					state.canvas_instance_batches[state.current_batch_index].shader_variant = CanvasShaderGLES3::MODE_PRIMITIVE;
				}
				_prepare_canvas_texture(state.canvas_instance_batches[state.current_batch_index].tex, state.canvas_instance_batches[state.current_batch_index].filter, state.canvas_instance_batches[state.current_batch_index].repeat, r_index, texpixel_size);
				for (uint32_t j = 0; j < MIN(3u, primitive->point_count); j++) {
					state.instance_data_array[r_index].points[j * 2 + 0] = primitive->points[j].x;
					state.instance_data_array[r_index].points[j * 2 + 1] = primitive->points[j].y;
					state.instance_data_array[r_index].uvs[j * 2 + 0] = primitive->uvs[j].x;
					state.instance_data_array[r_index].uvs[j * 2 + 1] = primitive->uvs[j].y;
					Color col = primitive->colors[j] * base_color;
					state.instance_data_array[r_index].colors[j * 2 + 0] = (uint32_t(Math::make_half_float(col.g)) << 16) | Math::make_half_float(col.r);
					state.instance_data_array[r_index].colors[j * 2 + 1] = (uint32_t(Math::make_half_float(col.a)) << 16) | Math::make_half_float(col.b);
				}
				_add_to_batch(r_index, r_batch_broken);
				if (primitive->point_count == 4) {
					
					_update_transform_2d_to_mat2x3(base_transform * draw_transform, state.instance_data_array[r_index].world);
					_prepare_canvas_texture(state.canvas_instance_batches[state.current_batch_index].tex, state.canvas_instance_batches[state.current_batch_index].filter, state.canvas_instance_batches[state.current_batch_index].repeat, r_index, texpixel_size);
					for (uint32_t j = 0; j < 3; j++) {
						int offset = j == 0 ? 0 : 1;
						
						state.instance_data_array[r_index].points[j * 2 + 0] = primitive->points[j + offset].x;
						state.instance_data_array[r_index].points[j * 2 + 1] = primitive->points[j + offset].y;
						state.instance_data_array[r_index].uvs[j * 2 + 0] = primitive->uvs[j + offset].x;
						state.instance_data_array[r_index].uvs[j * 2 + 1] = primitive->uvs[j + offset].y;
						Color col = primitive->colors[j + offset] * base_color;
						state.instance_data_array[r_index].colors[j * 2 + 0] = (uint32_t(Math::make_half_float(col.g)) << 16) | Math::make_half_float(col.r);
						state.instance_data_array[r_index].colors[j * 2 + 1] = (uint32_t(Math::make_half_float(col.a)) << 16) | Math::make_half_float(col.b);
					}
					_add_to_batch(r_index, r_batch_broken);