How can I get a permanent crosshair overlay on my viewport/editor mode?

This is getting super close to what I am looking for!!

I’ve made those connections and the Add node locks it horizontally… Great! Do you know how to lock the uv vertically?

When I change the value in the add node, it moves the crosshair from left to right, but how can I make it stop moving?

The value is the same, but the viewport is different and the crosshair moves.