  We study the linear stability problem to gravitational and electromagnetic
perturbations of the extremal, $ |\mathcal{Q}|=M, $ Reissner-Nordstr\"om
spacetime, as a solution to the Einstein-Maxwell equations. Our work uses and
extends the framework \cite{giorgi2019boundedness,giorgie2020boundedness} of
Giorgi, and contrary to the subextremal case we prove that instability results
hold for a set of gauge invariant quantities along the event horizon $
\mathcal{H}^+ $. In particular, we prove decay, non-decay, and polynomial
blow-up estimates asymptotically along $ \mathcal{H}^+ $, the exact behavior
depending on the number of translation invariant derivatives that we take. As a
consequence, we show that for generic initial data, solutions to the
generalized Teukolsky system of positive and negative spin satisfy both
stability and instability results. It is worth mentioning that the negative
spin solutions are significantly more unstable, with the extreme curvature
component $ \underline{\alpha} $ not decaying asymptotically along the event
horizon $ \mathcal{H}^+, $ a result previously unknown in the literature.
