The approach you should use to combat shader compilation stutter in Godot 4 is the same as in Godot 3: Show all effects behind a solid wall or sprite for 1 frame when the game loads.
Other approaches like ubershaders have been tried in Godot 3.x, but they were disabled in web exports because of bugs in browsers’ WebGL support. They also didn’t fully resolve shader compilation stutter, only reduce it.