How to fix 'Unchecked runtime.lastError: Could not establish connection. Receiving end does not exist.'

Question

I have the following error in the Chrome Dev Tools console on every page-load of my Node/Express/React application:

Unchecked runtime.lastError: Could not es

Answer 1

This was happening in Chrome for me and I discovered it was McAfee WebAdvisor. Once I disabled it, the message went away: