Here: If $f_k \to f$ a.e. and the $L^p$ norms converge, then $f_k \to f$ in $L^p$ is a proof for $1 \leq p <\infty$. Is the statement true for $L^\infty$ in general? Perhaps only on finite measures?
My first instinct was (on finite measure) to somehow use egorovs theorem. Since convergence in $L^\infty$ is equivalent to convergence almost uniformly. However, we need the measure to be $0$ and not $\epsilon$ as it is in the case of Egorovs.