### 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
p_mat2x4[0] = p_transform.columns[0][0];
	p_mat2x4[1] = p_transform.columns[1][0];
	p_mat2x4[2] = 0;
	p_mat2x4[3] = p_transform.columns[2][0];
	p_mat2x4[4] = p_transform.columns[0][1];
	p_mat2x4[5] = p_transform.columns[1][1];
	p_mat2x4[6] = 0;
	p_mat2x4[7] = p_transform.columns[2][1];
}
void RasterizerCanvasGLES3::_update_transform_2d_to_mat2x3(const Transform2D &p_transform, float *p_mat2x3) {
	p_mat2x3[0] = p_transform.columns[0][0];
	p_mat2x3[1] = p_transform.columns[0][1];
	p_mat2x3[2] = p_transform.columns[1][0];
	p_mat2x3[3] = p_transform.columns[1][1];
	p_mat2x3[4] = p_transform.columns[2][0];
	p_mat2x3[5] = p_transform.columns[2][1];
}
void RasterizerCanvasGLES3::_update_transform_to_mat4(const Transform3D &p_transform, float *p_mat4) {