Billboard shader help

Hi! I'm trying to implement a 3D billboard shader for sprites that preserves the sprite's original Z rotation and doesn't roll with the camera. I have a somewhat working solution, but the sprites start spinning at certain angles. Is it possible to eliminate this spinning? Thanks for any help! :)

shader_type spatial;
render_mode cull_back;

uniform sampler2D albedo_texture : source_color, filter_nearest;
uniform float transparency : hint_range(0.0, 1.0) = 0.0;

void vertex() {
	vec3 forward = normalize(normalize((INV_VIEW_MATRIX * vec4(0.0, 0.0, 1.0, 0.0)).xyz));
	vec3 right = normalize(cross(normalize(MODEL_MATRIX[1].xyz), forward));
	MODELVIEW_MATRIX = VIEW_MATRIX * mat4(
		vec4(right * length(MODEL_MATRIX[0]), 0.0),
		vec4(cross(forward, right) * length(MODEL_MATRIX[1]), 0.0),
		vec4(forward, 0.0),
		MODEL_MATRIX[3]
	);
	NORMAL = forward;
}

void fragment() {
	vec4 rgba = texture(albedo_texture, UV);
	ALBEDO = rgba.rgb;
	ALPHA = rgba.a * (1.0 - transparency);
}