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Understanding the dynamics of miscible viscous fingering is of paramount importance in a wide range of applications, from groundwater hydrology to enhanced oil recovery. In this work, we investigate the effect of precipitation and deposition of an initially dissolved component and the subsequent porosity and permeability variations on miscible viscous fingering in porous media. The commonly used stream function-vorticity formulation does not allow for nonsolenoidality of the velocity vector, which is the case when the porosity field varies with time. This is why we develop a velocity-vorticity formulation, making no further simplifications on the flow field. For numerical simulations, the governing equations are solved using the hybridization of pseudospectral and compact finite difference methods, and the time stepping is carried out through high-order semi-implicit schemes. Using our methodology, we tackle the problem of precipitation of an initially dissolved component through an infinitely fast and reversible reaction. It is found that the deposition of the formed precipitates in porous media results in more severe interfacial instabilities, the effect of which is attenuated as the viscosity ratio between the displacing and resident fluids increases. In addition, our results show that the formed precipitates are mostly concentrated around the interface where the two fluids actively mix. We also characterize the alterations of the local and global permeability fields, and interestingly, we find that the ultimate value of the overall permeability of the porous media scales linearly with the log-viscosity ratio at any fixed deposition rate. It is worth mentioning that, without loss of generality, the developed methodology and analysis in this study are applicable to other forms of precipitation reactions (e.g., finite rate and irreversible) in porous media.