How to make Makie plot react to two observales?

How can I make a Makie plot that is dependent on two observables, one variable dependent no the other, react when I change the master variable?

For Instance

using GLMakie, Makie

x = -10.0:.1:10.0
y = Observable(x .^2)

fig, ax, l = lines(x,y)
y[] = (rand()+1) .*y[]

Updates when I run the last line.

using GLMakie, Makie

x = Observable(-10.0:.1:10.0)
y = @lift($x .^ 2)

fig, ax, l = lines(x,y)
x[] = -10.0:.1:11.0

Doesn’t update even though y has updated?

The reason is that x is longer than y after the update, this is described here

It’s better to make one Observable{Vector{Point2f}} for example, so you can update both x and y components at once.