  Long-standing anomalous experimental results from short-baseline neutrino
experiments have persisted for decades. These results, when interpreted with
one or more light sterile neutrinos, are inconsistent with numerous null
results experimentally. However, if the sterile neutrino decays en route to the
detector, this can mimic $\nu_\mu \to \nu_e$ oscillation signals while avoiding
many of these external constraints. We revisit this solution to the MiniBooNE
and LSND puzzles in view of new data from the MicroBooNE experiment at
Fermilab. Using MicroBooNE's liquid-argon time-projection chamber search for an
excess of $\nu_e$ in the Booster beam, we derive new limits in two models'
parameter spaces of interest: where the sterile neutrino decays (I) via mixing
with the active neutrinos, or (II) via higher-dimensional operators. We also
provide an updated, comprehensive fit to the MiniBooNE neutrino- and
antineutrino-beam data, including appearance ($\nu_e$) and disappearance
($\nu_\mu$) channels. Despite alleviating the tension with muon neutrino
disappearance experiments, we find that the latest MicroBooNE analysis rules
out the decaying sterile neutrino solution in a large portion of the parameter
space at more than $99\%$ CL.
