### 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
vwptr[i * 12 + 5] = POLY_HEIGHT;
				vwptr[i * 12 + 6] = lr[i * 2 + 1].x;
				vwptr[i * 12 + 7] = lr[i * 2 + 1].y;
				vwptr[i * 12 + 8] = -POLY_HEIGHT;
				vwptr[i * 12 + 9] = lr[i * 2 + 0].x;
				vwptr[i * 12 + 10] = lr[i * 2 + 0].y;
				vwptr[i * 12 + 11] = -POLY_HEIGHT;
				iwptr[i * 6 + 0] = i * 4 + 0;
				iwptr[i * 6 + 1] = i * 4 + 1;
				iwptr[i * 6 + 2] = i * 4 + 2;
				iwptr[i * 6 + 3] = i * 4 + 2;
				iwptr[i * 6 + 4] = i * 4 + 3;
				iwptr[i * 6 + 5] = i * 4 + 0;
			}
		}
		if (oc->vertex_array == 0) {
			oc->line_point_count = lc;
			glGenVertexArrays(1, &oc->vertex_array);
			glBindVertexArray(oc->vertex_array);
			glGenBuffers(1, &oc->vertex_buffer);
			glBindBuffer(GL_ARRAY_BUFFER, oc->vertex_buffer);
			GLES3::Utilities::get_singleton()->buffer_allocate_data(GL_ARRAY_BUFFER, oc->vertex_buffer, lc * 6 * sizeof(float), geometry.ptr(), GL_STATIC_DRAW, "Occluder polygon vertex buffer");
			glEnableVertexAttribArray(RS::ARRAY_VERTEX);
			glVertexAttribPointer(RS::ARRAY_VERTEX, 3, GL_FLOAT, GL_FALSE, 3 * sizeof(float), nullptr);
			glGenBuffers(1, &oc->index_buffer);
			glBindBuffer(GL_ELEMENT_ARRAY_BUFFER, oc->index_buffer);
			GLES3::Utilities::get_singleton()->buffer_allocate_data(GL_ELEMENT_ARRAY_BUFFER, oc->index_buffer, 3 * lc * sizeof(uint16_t), indices.ptr(), GL_STATIC_DRAW, "Occluder polygon index buffer");
			glBindVertexArray(0);
		} else {
			glBindBuffer(GL_ARRAY_BUFFER, oc->vertex_buffer);