  Van der Waals (vdW) magnets are appealing candidates for realising spintronic
devices that exploit current control of magnetization (e.g. switching or domain
wall motion), but so far experimental demonstrations have been sparse, in part
because of challenges associated with imaging the magnetization in these
systems. Widefield nitrogen-vacancy (NV) microscopy allows rapid, quantitative
magnetic imaging across entire vdW flakes, ideal for capturing changes in the
micromagnetic structure due to an electric current. Here we use a widefield NV
microscope to study the effect of current injection in thin flakes ($\sim10$nm)
of the vdW ferromagnet Fe$_3$GeTe$_2$ (FGT). We first observe current-reduced
coercivity on an individual domain level, where current injection in FGT causes
substantial reduction in the magnetic field required to locally reverse the
magnetisation. We then explore the possibility of current-induced domain-wall
motion, and provide preliminary evidence for such a motion under relatively low
current densities, suggesting the existence of strong current-induced torques
in our devices. Our results illustrate the applicability of widefield NV
microscopy to imaging spintronic phenomena in vdW magnets, highlight the
possibility of efficient magnetization control by direct current injection
without assistance from an adjacent conductor, and motivate further
investigations of the effect of currents in FGT and other vdW magnets.
