Additive animation of text x and y with tref
Two values animations are added with additive sum for
x and y of text ('abcd') with a tref inside ('bc') with static
values for x and y.
The visible result is that the blue 'abcd' covers exactly the red 'abcd'
without any visible animation effect.
If something red gets visible, this indicates an error.
bc
a
b
c
d
ad