### 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
GLES3::MaterialStorage *material_storage = GLES3::MaterialStorage::get_singleton();
	canvas_begin(p_to_render_target, p_to_backbuffer);
	if (p_item_count <= 0) {
		
		return;
	}
	uint32_t index = 0;
	Item *current_clip = nullptr;
	GLES3::CanvasShaderData *shader_data_cache = nullptr;
	
	
	bool batch_broken = false;
	_new_batch(batch_broken);
	
	state.canvas_instance_batches[state.current_batch_index].start = state.last_item_index;
	index = 0;
	for (int i = 0; i < p_item_count; i++) {
		Item *ci = items[i];
		if (ci->final_clip_owner != state.canvas_instance_batches[state.current_batch_index].clip) {
			_new_batch(batch_broken);
			state.canvas_instance_batches[state.current_batch_index].clip = ci->final_clip_owner;
			current_clip = ci->final_clip_owner;
		}
		RID material = ci->material_owner == nullptr ? ci->material : ci->material_owner->material;
		if (ci->use_canvas_group) {
			if (ci->canvas_group->mode == RS::CANVAS_GROUP_MODE_CLIP_AND_DRAW) {
				material = default_clip_children_material;
			} else {