### 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
glDeleteTextures(1, &state.shadow_texture);
			glDeleteRenderbuffers(1, &state.shadow_depth_buffer);
			state.shadow_fb = 0;
			state.shadow_texture = 0;
			state.shadow_depth_buffer = 0;
			WARN_PRINT("Could not create CanvasItem shadow atlas, status: " + GLES3::TextureStorage::get_singleton()->get_framebuffer_error(status));
		}
		GLES3::Utilities::get_singleton()->texture_allocated_data(state.shadow_texture, state.shadow_texture_size * data.max_lights_per_render * 2 * 4, "2D shadow atlas texture");
		glBindFramebuffer(GL_FRAMEBUFFER, GLES3::TextureStorage::system_fbo);
	}
}
void RasterizerCanvasGLES3::render_sdf(RID p_render_target, LightOccluderInstance *p_occluders) {
	GLES3::TextureStorage *texture_storage = GLES3::TextureStorage::get_singleton();
	GLuint fb = texture_storage->render_target_get_sdf_framebuffer(p_render_target);
	Rect2i rect = texture_storage->render_target_get_sdf_rect(p_render_target);
	Transform2D to_sdf;
	to_sdf.columns[0] *= rect.size.width;
	to_sdf.columns[1] *= rect.size.height;
	to_sdf.columns[2] = rect.position;
	Transform2D to_clip;
	to_clip.columns[0] *= 2.0;
	to_clip.columns[1] *= 2.0;
	to_clip.columns[2] = -Vector2(1.0, 1.0);
	to_clip = to_clip * to_sdf.affine_inverse();
	glBindFramebuffer(GL_FRAMEBUFFER, fb);
	glViewport(0, 0, rect.size.width, rect.size.height);
	glDepthMask(GL_FALSE);
	glDisable(GL_DEPTH_TEST);
	glDisable(GL_BLEND);
	glDisable(GL_CULL_FACE);