So let's say you are doing a double slit experiment. Also, let's use electrons.

My question is, won't the gravity of the electron affect the earth, thereby causing it [decoherence](https://en.wikipedia.org/wiki/Quantum_decoherence) and its wave function to collapse (or for MWI, entanglement and loss of information to the environment, preventing interference)?

The reason why I think this would happen is because you could tell which path the electron took based off its tidal effects on the earth: everything is a detector.