We study the homogeneous Dirichlet problem for the evolution p(x, t)-Laplacian with the nonlinear source $$\begin{aligned} u_t-{\text {div}}\left( |\nabla u|^{p(x,t)-2}\nabla u\right) =f(x,t,u),\quad (x,t)\in Q=\Omega \times (0,T). \end{aligned}$$
u
t
-
div
|
∇
u
|
p
(
x
,
t
)
-
2
∇
u
=
f
(
x
,
t
,
u
)
,
(
x
,
t
)
∈
Q
=
Ω
×
(
0
,
T
)
.
Here, $$\Omega \subset {\mathbb {R}}^n$$
Ω
⊂
R
n
is a bounded domain, $$n\ge 2$$
n
≥
2
, and $$p(x,\!t)$$
p
(
x
,
t
)
is a given function $$p(\cdot ):Q\mapsto (\frac{2n}{n+2},p^+]$$
p
(
·
)
:
Q
↦
(
2
n
n
+
2
,
p
+
]
, $$p^+<\infty $$
p
+
<
∞
. It is shown that the solution is stable with respect to perturbations of the exponent p(x, t), the nonlinear source f(x, t, u), and the initial datum. We obtain quantitative estimates on the norm of the difference between two solutions in a variable Sobolev space through the norms of perturbations of the exponent p(x, t) and the data u(x, 0), f. Estimates on the rate of convergence of solutions of perturbed problems to the solution of the limit problem are derived.