Measurements of weak gravitational lensing at low redshifts (z≲0.5−1), quantified by the parameter S_8, favor weaker matter clustering than that expected from the standard ΛCDM cosmological model with parameters determined by cosmic microwave background (CMB) measurements. However, the amplitude of matter clustering at higher redshifts, as probed by lensing of the CMB, is consistent with ΛCDM. This apparent paradox suggests a connection between the S_8 tension and the transition from matter to dark-energy domination. In this talk, I will show that the tension can be resolved by introducing a friction between dark matter and dark energy without altering the tightly constrained expansion history. The low-S_8 measurements favor (at ≳3σ, in this one parameter model) a non-zero drag leading to a suppression of low-redshift power right around the transition from matter to dark-energy domination.