Tested versions

Godot v4.4.stable

System information

Godot v4.4.stable - Windows 11 (build 26100) - Multi-window, 2 monitors - Vulkan (Forward+) - integrated Intel(R) Iris(R) Xe Graphics (Intel Corporation; 32.0.101.5768) - 13th Gen Intel(R) Core(TM) i7-1355U (12 threads)

Issue description

shader_type canvas_item;
uniform sampler2D screen_texture: hint_screen_texture, filter_nearest;

void fragment() {
	COLOR = texture(screen_texture, SCREEN_UV + cos(TIME)/SCREEN_UV.y/20.0);
}

The following shader behaves differently between compatibility and forward+

Compatibility: Color blending, screen texture not nearest filter.

Forward+: No Color blending, screen texture is nearest filter.

Steps to reproduce

Use a screen reading texture on compatibility renderer, have the texture distort.

Minimal reproduction project (MRP)

example.zip

I used zoomed in pixel art for the example, at 1x scale pixel art is much worse.