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Radio very-long-baseline interferometry has for many decades provided extremely high-precision (sub-milliarcsecond) astrometry comma maintaining the absolute celestial reference frame used by all astronomers. Only recently comma with the launch of ESA.s Gaia mission comma has this been matched at optical wavelengths. An analysis of more than 11890 Gaia position matches to radio quasars in the VLBI Absolute Position Catalog has revealed 12% to have significant (> 5 sigma) position offsets. The most extreme of these range from a few to several hundred milliarcseconds comma and the offset distribution shows a strong anisotropy in the direction of the radio jet. This is not due to radio structure as interferometric positions refer with high precision only to the compact core or jet base. Extensive arguments presented in several publications show that the most likely origin for the offsets are bright optical jets of 100 mas extent or more comma which have not previously been predicted by theory. Other potential scenarios comma such as dust obscuration in the host galaxy or dual AGN are thought to be a far less likely origin comma but only HST can confirm this. We propose HST snapshots of a sample of 75 carefully selected sources (expected sample of 25 observed) to test the hypothesis that significant position disagreements between two flagship astrometry programs are due to the presence of unexpectedly strong optical jet emission.